TO PRUNE, PINCH, SHEAR, CUT BACK, DEADHEAD, DEADLEAF HERBACEOUS PERENNIALS OR NOT?

Perennials are non-woody plants that live for more than one year, usually with their foliage and stems dying back in fall or winter, and returning the following spring from roots that survive underground. The term "perennial”, is used to describe herbaceous plants that die back to the ground each winter, as opposed to woody plants like trees and shrubs. While there are both flowering and nonflowering varieties of herbaceous perennials, they are most often associated with flowering plants.

Perennials in your landscape are like dessert. They can balance and complement, much like a delicious dessert rounds out a meal. Perennials provide an immense variety of color, foliage, texture, and form. Flowering perennials bloom at different times, creating a delightul display from spring through fall.

Pinching, shearing, cutting back, deadheading, and deadleafing are all pruning techniques. All of these actions can be beneficial for herbaceous perennials, and are specific to each type of plant, but the necessity and frequency depend on the specific plant and your gardening aspirations. 

A moderate amount of maintenance is needed to keep a garden looking tranquil and organized. A minimal effort may mean the difference between a garden that is lackluster and one which brings you comfort and pleasure.

“Lest you worry that the following suggestions will burden you with an even longer to-do list, try to think of maintenance in the perennial garden as simply gardening.” - This is sage advice from Ramsey County, Minnesota Master Gardeners blog post.

Pinching - Pinching is a type of pruning that is mostly done on young plants by removing the growing tip (terminal bud) of a stem or branch and the first set of leaves. This can be done with your fingers (thumbnail and forefinger) or hand pruners. The purpose is to encourage bushier growth by redirecting the plant's energy into developing side shoots, leading to a fuller, more compact plant. Pinching also promotes more blooms while it delays or extends blooming time. Pinch the stem tips back once or twice in late spring or early summer, but no later than early July.

Shearing - Cutting entire plants back by 25-50% after they finish blooming is a pruning option that benefits some perennials. This pruning can be done with hand pruners or hedge shears. There are perennials that rebloom after being sheared; others will not rebloom, but will produce a fresh flush of young foliage. This type of pruning is ideal for perennials with lots of tiny flowers that bloom all at once. Plants should be sheared as soon as flowering begins to taper off - no later than early August.

Deadheading - A process of pruning with the removal of dead flowers on perennials is done throughout the growing season as blooms fade. The reasons for deadheading are specific to each type of perennial (not all flowers require deadheading). For some, removing dead flowers improves appearance, or can extend bloom time, stimulate rebloom, or promote the health of the plant. Most perennials will not rebloom with deadheading, although many perennials can continue to produce flowers for a longer period of time if they are not allowed to go to seed. Deadheading isn’t difficult, but it can be time- consuming. Faded flowers can be pinched off or cut with hand pruners. Some perennials produce flower stalks that are separate from the rest of the foliage. For these, the entire flower stalk is cut back to the base of the plant.                            Lastly, guidance from Gladys Fowler of the Peterborough Horticultural Society in Ontario, Canada. “Perennials like purple coneflower, bee balm, sedum; Siberian iris, Joe Pye weed and rudbeckia have ornamental seedheads. These not only provide interest in the garden through fall and winter, they also provide food for birds. Remove two thirds of the seedheads and leave one third on the plant.”

Cutting entire plant back - This pruning method can be done on some spring blooming perennials like Dicentra (bleeding heart) and, bulbs like daffodils and tulips, and rhizomes, like iris where the foliage has died back and the plant begins its dormancy. While not necessary for plant health, it can be done for aesthetic reasons, and should only be done after the foliage naturally fades. Cut the foliage to the ground, leaving about an inch sticking through the soil.

Deadleafing - Deadleafing is the removal of dead leaves. It is a term popularized by garden writer Tracy DiSabato-Aust in her seminal book The Well-Tended Perennial Garden. Aptly described by the Piedmont Master Gardeners Association, “It simply refers to pinching or snipping off leaves that are dead or damaged due to sun scorch, lack of water, disease, insect and animal chewing, or weather. It also refers to cleaning up dead foliage from spring-flowering bulbs such as daffodils or tulips.”                          Why remove dead leaves? The results are improved appearance, disease prevention, and promotes growth.

It is useful to research the specific characteristics and needs of each perennial to determine the most beneficial approach, and then establish a routine for regular maintenance pruning.

Recommended reading: The Well-Tended Perennial Garden – An essential guide to planting and pruning techniques, Third Edition, (DiSabato-Aust, Tracy, 2017)

THE FATE OF RHODODENDRONS - WINTER BURN AND THERMONASTY

Winter burn is a form of damage to the leaves. Thermonasty, a natural phenomenon, is leaf movement in response to cold temperatures.

Evergreen trees and shrubs can have either needle-like or broad leaves, with examples of needle-leaved evergreens including pines, spruces, and firs, while broadleaf evergreens include boxwoods, hollies, and rhododendrons. 

Winter burn - is a common problem of evergreens trees and shrubs, especially rhododendrons. Leaves do not actually burn but rather dry up. Leaves turn yellow or brown, and crispy in response to low soil moisture, freezing temperatures and blowing wind. On a windy winter day broadleaf evergreens can become water deficient in a few minutes. These evergreen plants hold on to their foliage in winter, and need tons of moisture to keep their leaves green throughout the season. Since the ground is frozen, plant roots are not able to take up enough water from the soil to replace the lost moisture. Winter injury may occur when water is transpired through plant tissue more quickly than it can be absorbed through the roots. A rapid drop in temperature after a warm and sunny winter day can also cause further injury to the plant.

Sean McNamara, owner of Redding Nursery confirms, “Yes, I’ve seen winter burn damage all over Fairfield County. The extreme drought in the fall, followed by a very cold winter, has caused significant damage to broadleaf evergreens. We definitely need more rain—hopefully, things will recover, but only time will tell. Feeding plants with Holly-tone fertilizer can help, but the most important factor is adequate water.”

Thermonasty - is a form of leaf movement that occurs as a response to changes in temperature. The movement is nondirectional, meaning quick responses that do not involve growth towards a stimulus. When rhododendron leaves become curled and droopy, it’s due to the results of thermonastic movement, a unique adaptation in rhododendrons. These are two distinct, reversible leaf movements responding to different environmental pressures : leaf curling, and changing leaf angle (drooping).

Normally, rhododendron leaves are flat and extend horizontally from the plant. During lower winter temperatures, the nastic movements of rhododendron leaves begin - The significance of winter leaf curling is to reduce the rate of re-warming following leaf freezing. Rhododendron leaves can freeze and thaw multiple times and survive, but only if the thaw is drawn out and gradual. Curling, by reducing the surface area, slows thawing down.

Changing leaf angle in rhododendrons helps to protect the leaves from damage during the winter when sunlight hits the leaves when they are cold, and the plants are dormant and not photosynthesizing.

• Above 40 degrees: leaves are horizontal, open and taking in the sunlight.

• 40 - 34 degrees: the leaves begin to hang downward and dangle, but don't really start to curl yet.

• 33 - 25 degrees: the leaves start to curl inward.

• Below 25 degrees: the leaves wrap up tightly.

Once temperatures rise, the leaves will gradually stretch right back out to their normal position.

Rhododendron care - Proper care during the growing season is a crucial part of keeping rhododendrons alive through the winter.

Soil and Moisture - Rhododendrons require soil that is moist, well-drained, acidic, and rich in organic matter. Since rhododendrons are shallow rooted plants, it is easy for them to dry out due to lack of water, or rot if over-watered. Sandy, silty, or clay soils should be amended before planting by adding peat moss or compost.

Fertilizer - Rhododendrons require little supplemental feeding, especially when the soil is rich in organic matter. Use a fertilizer designed for acid-loving plants, such as Holly-tone, and apply in late winter or early spring. Do not over-fertilize. The American Rhododendron Society advises, “Excessive fertilization can result in damaged roots and leaves, and some rhododendron varieties can be killed with fertilizer.”

Mulching - Rhododendrons have shallow, fibrous roots and benefit from a thin layer of mulch to protect the roots.

Pruning - Rhododendrons rarely require pruning, especially when planted in the proper location. Dead branches can be pruned at any time of year and if growth becomes excessive,the size can be reduced with light pruning; best done soon after flowering.

Conclusion - What is the ongoing outcome for the affected leaves on rhododendrons? Will they uncurl and reverse angle? Will they die? Will they fall off? Will they regrow new leaves?

Sean McNamara’s response, “It remains to be seen. I don’t ever remember a drought so severe in the fall. The rhododendrons continuing to stay curled now that the temperatures are warm is due to the drought. I predict that newly planted rhododendrons and those dealing with other problems may not survive.  Most, if they were well established and otherwise healthy, should put out new growth in May and June. Those suffering from very bad winter burn will look unsightly until the new growth emerges. We shall see…”

HOW TO KEEP YOUR LAWN HEALTHY IN SUMMER

The hot weather in the summer months can severely damage lawns. Without proper care from June to September, the stress from excessive heat and drought can cause grass to dry out and turn brown. A stressed lawn becomes susceptible to weeds, insects, and disease. Maintaining a healthy lawn during the summer months requires attention to watering and mowing, and monitoring for weeds, insects and disease.

Watering - The heat of the summer sun can damage a lawn quickly as moisture evaporates. Moisture is very important for a healthy lawn, and while there may be periods of adequate rainfall, there will likely be periods of drought. So it’s important to water when rainfall is scarce. The best time to water a lawn is in the morning, compared to watering during the hotter part of the day. This reduces evaporation and helps the grass remain hydrated and cooler throughtout the day, thereby decreasing the risk of heat stress.   

Deep, infrequent watering is better than shallow, frequent watering. It helps promote strong, deep root systems and creates a lawn more drought tolerant, as opposed to frequent short watering which creates weak, shallow roots. Lawns should receive roughly one inch of water each week, whether from rainfall, irrigation, or a combination of both. This is equal to three 20 to 30 minutes watering sessions weekly.

Mowing - One of the most common summer lawn care mistakes is cutting grass too short.

Scalping the lawn can weaken it, making it more vulnerable to heat stress, weeds, and disease. Set the mower blade higher in the summer months. For the healthiest lawn, 3.5 to 4 inches is most desirable, and a general rule is not to cut more than one third of the grass blade each time you mow. Leave the clippings on the lawn; they will decompose and help feed the grass. Taller grass shades the soil reduces evaporation, and promotes deeper roots. The result is a lawn that is more heat and drought tolerant, has reduced weed growth, and is more robust.

Dormant lawns (those that have turned brown) should not be mowed.

Keeping the mower blade sharp is crucial for a healthy lawn. A sharp blade makes clean cuts, like scissors. A dull blade tears the grass, causing damage and stress. Sharpen or replace the lawn mower blade on a regular basis.

Weeds - Summer weather accelerates weed growth. Regularly inspect your lawn and hand-pull weeds as soon as you discover them. This is an effective method for small areas. To prevent regrowth, remove the entire root system. A healthy lawn is a natural defense against weeds. Weeds are crowded out and prevented from establishing themselves.

Insects and disease control - Monitor your lawn for any signs of insects or disease. Early detection is key because these issues caught too late can lead to widespread damage.

Proper watering, mowing, and monitoring for weeds, insects and disease - following these tips will be the best defense to keep your lawn healthy in summer.

TORTURED GARDEN SOCIETY

CARLO CRIVELLI (1435 - 1495) Detail - St. Augustine

Tortured Garden Society founder Terry Karpen is the last person you would want to be trapped in a car with during a drive through residential neighborhoods. This is because you would have to endure listening to a relentless commentary on the subject of distressing and improper gardening practices in the landscape. As the founder and sole member of a small secret society of a professionally trained gardener, she knows firsthand the distress she experiences.

Here are some improper gardening practices that torture her the most -

Fallen leaves blown away - Bare, scorched earth left behind after overly ambitious fall and spring cleanups. What’s left behind is an invitation for every opportunistic weed and invasive plant looking for a new home.

“The annual ritual of raking, blowing, piling, bagging and removing leaves costs each homeowner – or their landscaper – hours of time each fall. It also robs the yards of one of nature’s greatest resources: rich, natural compost.”

- https://www.leaveleavesalone.org

Bad pruning - A common belief is that it is mandatory for boxwoods and other shrubs to be drastically sheared into balls or flat-topped hedges for optimum maintenance. This is actually incorrect. Incorrect pruning accounts for most work done by homeowners and professionals alike. There are so many things to consider, from pruning time, the amount of pruning, to the correct cuts that need to be done. Correct pruning is a science and an art.

Tree topping - This torturous landscape practice is not only bad for the long-term health of a tree, it’s unattractive!  Tree topping is the practice of removing whole tops of trees or large branches. The tree’s ability to photosynthesize becomes compromised, and in an effort to survive, the tree grows new shoots and foliage as quickly as possible. This new growth, called water sprouts, is usually weak and regrows every time they are cut off. Lamentably, the tree becomes deformed and no longer provides beauty to the landscape.

Volcano mulching - “Mulch volcanoes" are extremely harmful to the health of trees. Over-mulching in the shape of a mound around the trunk of the tree is pejoratively referred to as a mulch volcano. Mulch is piled up so high that the trunk flare is buried. The trunk flare is the base of the tree which tapers out just above where the root system begins. A buried trunk flare will lead to disease, decay, root rot and the eventual death of the tree.

Why mulch can be beneficial - Mulch conserves soil moisture, moderates soil temperature, reduces growth of weeds, helps protect soil from erosion, prevents frost heaving in winter and adds organic matter to the soil as it breaks down. Mulch makes garden beds and landscapes look more tidy and attractive.                                                       Apply the mulch around the tree to a depth of two to four inches, making sure there is no mulch within four to six inches of the base of the tree. The mulch should be spread out almost flat. All of this applies for shrubs and perennials as well.

Bad soil - Topsoil and loam soil (garden soil) are not the same. Loam soil is topsoil that has been enriched to make it better suited for plant growth. This is a mix of local topsoil and organic matter. This is the healthy soil that is the foundation of a healthy garden.

Poor Planting Practices -  Incorrect planting examples are choosing the wrong planting site, low quality plant, the planting hole is too small, planting too deep, planting too high.

Cutting wet lawns - Cutting wet grass can damage the roots and soil, or spread fungal disease. Mowers can compact saturated soil or cause ruts to form.

Landscape fabric - Some of the cons of using landscaping fabric include:

Landscape fabric is not a permanent solution. Over time, it will degrade, break down, poke through the soil/mulch, and become unsightly. Soil and mulch installed on top of the fabric prohibit adequate amounts of water and air to reach plant roots, leading to the plant’s decline. In fact, pulled up landscape fabric after a deep soaking rain, can reveal dry soil beneath. The fabric also acts as a barrier to decomposing soil and mulch that cannot be incorporated because of the fabric, which leads to unhealthy soil. And the worst offense of landscape fabric is that weeds can still grow in the soil or mulch on top of the fabric, and some weeds succeed in growing through the fabric.

Loud leaf blowers - Some produce as much noise as a plane taking off. The majority of leaf blowers emit pollutants linked to cancers, heart disease, and asthma, and blast air many miles per hour, eroding topsoil and sending pollen, fertilizers, and herbicides adrift. U.S. cities and towns are taking action to limit gas-powered blowers.

Unskilled landscapers - Many landscaping companies offer services

beyond their expertise and they are ignorant about their lack of knowledge.

Cookie cutter garden design - There exists a “paint-by-number” approach to gardens and landscapes due to lack of knowledge on the elements of design. And there is an enormous variety of plants to choose from at the present time, making it unnecessary to rely on overused selections.

Outdoor lighting - If you lived in Redding twenty years ago it was uncommon to encounter outdoor lighting beyond a light fixture by the front door, or a lamp post in the driveway, and even more rare for any lights to remain on all night. With almost zero crimes, safety was not in question. Observing the night sky was a treasured feature of living in Redding. Very gradually, the trend has grown to all-night lighting, even though Redding has significantly lower rates of crime than the national average. And currently outdoor lighting is not just low wattage front door light fixtures, now there are floodlights and spotlights. Many of these high-output fixtures beam the light far distances.   

Light pollution, an excess of artificial light is a global issue affecting human health, wildlife behavior, and plant life. Artificial light can disrupt natural body rhythms in both humans and animals. It disrupts the migration pattern of birds by disorienting them. In recent studies scientific reports show that insects are attracted to lights which interferes with their natural way of knowing what direction is “up” while flying. A 2019 study released by Biological Conversation shows excess outdoor light is impacting how insects hunt, mate and makes them more vulnerable to predators. While impacts are still being studied, scientists do know exactly how light pollution is affecting the ways plants grow and reproduce. It disrupts their seasonal rhythms and the ability to sense and react to natural light, as well as the fragile relationship with pollinators.

Plant labels not removed from plants - Would you go out in public with labels still attached to your clothes?

“Right is right even if no one is doing it; wrong is wrong even if everyone is doing it.”     - St. Augustine

To learn more: www.healthyyards.org

THE TREE OF LIFE - PLANTS

The affinities of all the beings of the same class have sometimes been represented by a great tree. I believe this simile largely speaks the truth. -  Charles Darwin

The tree of life is used to explain the evolution of relationships between the different species on Earth.

In 2015 scientists released a first draft of a new "tree of life," demonstrating how the world's 2.3 million species of animals plants, fungi and microbes are connected. The project, a collaborative effort among eleven institutions, supported by a grant from the U.S. National Science Foundation was published online September 18, 2015 in Proceedings of the National Academy of Sciences. The research depicts the relationships among living things as they diverged from one another over time, tracing back to the beginning of life on Earth more than 3.5 billion years ago.

On April 24 of this year, the most comprehensive "tree of life" to date for flowering plants was presented in a new study published in Nature by an international team of 279 scientists. Using 1.8 billion letters of genetic code from more than 9,500 species covering almost 8,000 known flowering plant genera this achievement sheds new light on the evolutionary history of flowering plants and their rise to ecological dominance on Earth. The open access article is titled “Phylogenomics and the Rise of the Angiosperms”. https://www.nature.com/articles/s41586-024-07324-0

The flowering plant tree of life

Plants that fruit or flower are called angiosperms and account for about 90% of all known plant life on land. The most numerous of all the divisions in the Plant Kingdom, they are found virtually everywhere on the planet. In comparison, gymnosperms are flowerless plants that produce cones and seeds. Gymnosperms include the conifers, cycads, and ginkgo.

Flowering plants emerged over 140 million years ago, after which they rapidly overtook other vascular plants. Darwin was puzzled by the seemingly sudden appearance of such diversity in the fossil record and wrote: "The rapid development, as far as we can judge, of all the higher plants within recent geological times is an abominable mystery." The question of how flowering plants were able to develop this dominance has occupied researchers to this day. This study sheds insights into their origins and relationships. Besides well-known plant types found on Earth today they also examined the genetic codes of centuries-old specimens and already extinct examples.                                                                                                                                 Herbariums conserve plants and plant parts for scientific purposes in dried or pressed form. The DNA of these dried plants can be isolated and used for analysis.                    Seed banks, where seeds are stored to preserve genetic diversity for the future, are also important to the research work - centuries-old seeds can be germinated and studied.

The research team, led by scientisits at the Royal Botanic Gardens, Kew, in the UK, believes the data will contribute to identify new species, refine plant classification, uncover new medicinal compounds, and conserve plants in the face of climate change and biodiversity loss. Scientists who collaborated on the project noted, “The sheer amount of data unlocked by this research, which would take a single computer 18 years to process, is a huge stride towards building a tree of life for all 330,000 known species of flowering plants—a massive undertaking by Kew's Tree of Life Initiative. Open access will also help scientists make the most of the data, such as combining it with artificial intelligence to predict which plant species may contain molecules with medicinal potential. Similarly, the tree of life can be used to better understand and predict how pests and diseases will affect plants in the future. Ultimately, the researchers note, the applications of this data will be driven by the ingenuity of the scientists who access it.”

HOW THE ENVIRONMENT AFFECTS PLANT GROWTH

ct.gov/CAES= photo credit

“Spring has newly sprung the hills are full of grass…” -Ogden Nash

The warmer weather invites you to walk outside, listen to birds sing and inspect your landscape. That’s when you might observe, “What’s wrong with my rhododendron? Why do my boxwood shrubs have dead leaves? Why are the tips of the needles on my pine tree rust-colored?” The answer is- winter injury called “winter burn”. Winter burn is a common problem of needle evergreens, such as hemlock, arborvitae, chamaecyparis, pine, and juniper, and those with “broad leaves”, like boxwood, hollies, and rhododendrons. Leaves do not actually burn but rather dry up. Leaves turn yellow or brown in response to low soil moisture, freezing temperatures and blowing wind. On a windy winter day broadleaf evergreens can become water deficient in a few minutes. Evergreen plants hold on to their foliage in winter, and need tons of moisture to keep their needles or leaves green throughout the season. Since the ground is frozen, plant roots are not able to take up enough water from the soil to replace the lost moisture. Winter injury may occur when water is transpired through plant tissue more quickly than it can be absorbed through the roots. A rapid drop in temperature after a warm and sunny winter day can also cause further injury to the plant.

As described by Dr. Sharon Douglas at The Connecticut Agricultural Experiment Station, “The factors that contribute to winter injury are diverse and results often do not appear on woody ornamentals until the following spring and summer. In addition, the extent and severity of the injuries that develop are often more extreme on plants weakened from drought stress, transplant, or from other environmental and site-related stresses.”

Environmental factors affecting plant growth-  Most plant problems are caused by environmental stresses. The main factors that affect plant growth are light (sunlight), temperature, moisture and nutrients. Each of these factors can cause beneficial or detrimental effects. The detrimental effects manifest as symptoms, the visible reaction or alteration in a plant that result from the plant being sick or injured.

Light-  Photosynthesis, the process by which plants transform light energy into chemical energy, is dependent on quantity, quality, and duration of sunlight.

Temperature-  Air temperature affects the rate of photosynthesis, the production of food molecules for energy. Air temperature also affects respiration, the burning of food molecules for energy. Soil temperature affects the rate of nutrient absorbtion and root growth.

Moisture-  Excess or insufficient moisture affects the rate of nutrient absorption, as water is the transporter of nutrients. Water is necessary for photosynthesis. Plants still need water during the winter, and when the soil is frozen, the movement of water into the plant is severely restricted.

Nutrients- Excess or insufficient nutrients can have adverse effect on plant growth.

Other environmental factors can be poor planting or mulching practices, mechanical damage from mowers or trimmers, chemical injury from pesticide application, and pollution.

All environmental stress factors are referred to as abiotic, meaning they are non-infectious, non-living; rather than biotic factors such as bacteria, fungi, and insects.

Are your plants going to survive from winter burn?-  The signs of winter injury usually don’t appear until months after the winter season. Identification can be difficult because it can look different in every plant. Plants with winter burn usually survive. Once the ground thaws, damaged plants can recover by watering them well if there has not been adequate rainfall. While there is no remedy for damaged areas, new needles or leaves sprout and replace the dead ones.

“Pruning out the browned parts will have different effects on different species of evergreens,” according to Doris Taylor from The Morton Arboretum in Illinois. “A yew or a boxwood can sprout new growth from farther down a branch if you cut off the end, but a pine can only grow from a bud at the branch tip. If you cut that off, the branch will never grow longer.” Taylor recommends, “Don't rush to prune out branches that may not really be dead. On many plants, the leaves are discolored but the buds are still alive. That means the branch is still alive too."

It is best to wait until late May to determine what is alive and what isn’t. Needles or leaves that are affected by winter burn, will drop off on their own as the season progresses.

Winter burn prevention-  All plants, and especially evergreens, need to be fully hydrated in fall, all the way up until the ground freezes. And applying three to four inches of mulch at the base of trees and shrubs can also be beneficial since it helps to conserve moisture during the winter.

Now it’s time to celebrate nature, and spend time outdoors to walk or rest, think or dream, or sit under a rustling tree, smell the flowers, and listen to birds sing.

SOIL IS ALIVE; DIRT IS DEAD

There is a big difference between soil and dirt. They are different regarding composition. Soil is alive- there are more species of organisms in the soil than there are above ground. A single handful of soil contains millions of individual living organisms.    

Dirt is dead soil, void of any nutrients or living organisms that plants need to grow.

Basics of soil -

Soil is classified into four types based on their texture: sandy, silt, clay, and loamy. The different types of soil are categorized based on the size of the particles and the percentage of particles present in them. Loamy soil is a combination of sand, silt and clay and as a result, the beneficial properties of each are included. Loamy soil has a high content of organic matter and the ability to retain moisture and nutrients making it ideal for plant growth. Other types of soil are based on the percentage of particles, resulting in more compound types of soil: loamy sand, sandy clay, silty clay, etc.                            

What is topsoil? -

Literally, topsoil is the natural upper layer of soil and usually extends to a depth of two to ten inches. All soils are not created equal and not all topsoils are created equal. Topsoils can differ dramatically. The best topsoil has an adequate proportion of sand, silt, and clay, and has a high concentration of organic matter, as well as high levels of microbial activity. It is commonly referred to as loam soil or garden soil.

◆There is no legal definition of the word topsoil.                                                  

◆When you buy topsoil do you really know what you are getting?                                

“In the landscape materials industry, topsoil refers to earth that has gone through a screening process to remove debris and create a consistent texture,” aptly described on the company TheDirtBag website.                                                                

◆Topsoil and loam soil (garden soil) are not the same. Loam soil is topsoil that has been enriched to make it better suited for plant growth. This is a mix of local topsoil and organic matter. This is the healthy soil that is the foundation of a healthy garden.

A WALK THROUGH WINTER FOLIAGE

What happens to fallen leaves in winter?

Even after they fall to the ground, leaves serve a purpose. Leaves decompose at the feet of trees and return nutrients to the soil that will support the trees’ spring growth. In winter, microbes and insects come into contact with the dead leaves, breaking them apart both chemically and physically. This is called the nutrient cycle.

If all the leaves are removed from the ground, it takes away the natural source of organic matter that helps enrich the soil. And fallen leaves help protect the soil from erosion by adding to its water-holding capacity, allowing more water to infiltrate into the ground, especially important during extreme weather events and flooding.

Once trees have shed their leaves, they enter a period of dormancy during the winter months and are, essentially, asleep.

Winter dormancy

How do trees survive the winter? Trees prepare for winter by sending their most vital nutrients down to their roots.

While sleeping, trees metabolic activity slows down and they conserve energy, surviving on basic maintenance processes, rather than active growth and photosynthesis. Trees live off stored sugars for sustenance. The sugars preserve the health of the roots and vascular system, and also act like an antifreeze, decreasing the freezing point of individual cells within trees.

Trees remain in this dormant state until the days lengthen again. This seasonal cycle of shedding old leaves and growing new ones allows them to survive.

"In the end we will conserve only what we love, we will love only what we understand, and we will understand only what we are taught." – Baba Dioum, a conservationist and environmentalist, in a 1968 speech to the International Union for the Conservation of Nature and Natural Resources.

A WALK THROUGH FALL FOLIAGE - Part two

Photosynthesis is the most important biological process on earth. Plants require photosynthesis for their survival, and our existence depends on that process. The main function of photosynthesis is to convert solar energy into chemical energy and then store that chemical energy for future use. That chemical energy is stored as glucose (a form of sugar). Chlorophyll, the green pigment in leaves, absorbs sunlight which is then used to convert carbon dioxide from the air and water into glucose (sugar) and oxygen. 

In autumn, as the days shorten and temperatures fall, the seasonal change signals for the plant to produce less chlorophyll, eventually producing none at all. The plant starts to mobilize resources from the leaves and withdraw them to the woody, more permanent parts to be available next season. This process, called photoperiodism, of going into dormancy starts before the leaves begin to change colors, and begins the processes leading up to their fall from the trees. Seasonal cooler temperatures at night cause the veins in leaves that carry fluids into and out of the leaf to gradually close off as a layer of cells forms at the base of each leaf. These clogged veins trap sugars in the leaf and reward us with brilliant autumn leaf colors.

A WALK THROUGH FALL FOLIAGE

Deciduous is the word used for the trees and shrubs that shed their leaves at the end of each growing season. The word deciduous is from the Latin word decidere, meaning “to fall off.”

Plants respond to their environment in a variety of ways and rely on chemical messengers (hormones) that affect all aspects of plant life. The interaction of these hormones regulates different stages of plant growth. Plant hormones control the process of going into dormancy, which starts before the leaves begin to change colors.

Most plants are green, the result of chlorophyll, a green pigment, and responsible for the absorption of light to provide energy for photosynthesis. When autumn arrives, chlorophyll levels drop, a signal that triggers the release of a series of hormones. Auxin is the primary plant growth hormone, produced in the roots and shoots of a plant. As the days shorten and temperatures fall, signals for the plant to stop using energy to grow lead to the reduced production of auxins. As auxin levels decrease, the hormone ethylene is activated and begins the process of recycling the leaf - senescence. The process of leaves changing colors in the fall is called "senescence." It's a natural process where the green chlorophyll pigments in the leaves break down and reveal other pigments, which give the leaves their autumn hues. These pigments have been present within the leaf’s structure all along but masked by the dominant green of chlorophyll. Most deciduous trees and shrubs begin to show their “true” colors in autumn. The four primary pigments that produce color within a leaf are: chlorophyll (green), xanthophylls (yellow), carotenoids (orange), and anthocyanins (reds and purples).

In deciduous trees and shrubs entering dormancy, the leaf separates from the plant at the “abscission layer” located at the base of the leaf stem (petiole). The hormonal changes described above lead to changes in cell walls throughout the leaf stem that eventually lead to leaf drop.

Leaves that tend to hang on to their twigs are known as “marcescent leaves”. In marcescence, the abscission zone does not develop until the leaf bud breaks in the spring. Trees that exhibit marcesence include oak, beech, and hornbeam trees.

Do fallen leaves have a benefit?

Words of wisdom from Leave Leaves Alone, located in Bedford Hills, NY - “The Many Ways Leaves Can Be Used in the Landscape: Natural mulch, protect roots, suppress weeds, amend soil, support biodiversity, fertilize naturally, encourage mycorrhizae (beneficial fungal growth in the soil).”

The greatest way to benefit your garden and the environment is to leave the leaves.

As the leaves decay, they add organic matter back into the soil, which lessens the need for fertilizer. The leaves also provide winter habitat for wildlife including birds, turtles, frogs, and insects (butterflies, bees and other pollinators) that overwinter in the fallen leaves.  If the leaves are removed, these creatures will not survive.

VERSATILE HYDRANGEAS - Part two

When and How to Prune Hydrangeas

Before grabbing the pruning tools, it is important to identify which species you have. There are six species of hydrangeas that are commonly grown in American gardens and all of them have very different growth habits and pruning requirements.

Hydrangea macrophylla Bigleaf Hydrangea

Native Range: Japan
Old-fashioned varieties of bigleaf hydrangea flower on old wood (the previous year’s growth) and require no pruning.

Dead flowers can be cut off at any time of year.

Because bigleaf hydrangeas bloom on old wood, flower buds are sensitive to a sudden freeze after a period of warm temperatures in the spring. If those buds are damaged, the shrub may not produce flowers.

The first bigleaf hydrangea to bloom on old and new wood, was introduced in 2004, extending the bloom season. This introduction enables plants to bloom regardless of winter damage or pruning mistakes. “Bigleaf hydrangeas that bloom on old and new wood are known as reblooming, or remontant, hydrangeas, since they bloom first on their old wood, then after a brief rest for some vegetative growth, create flower buds on that new growth that open in the following weeks”, as described on the website Hydrangeas.com.

All varieties of bigleaf hydrangea should be pruned to remove dead canes (stems). Cut these down to the ground.

Hydrangea arborescens Smooth hydrangea

Native Range: Eastern North America

Smooth hydrangeas bloom on new wood and will tolerate heavy pruning. Cut a third of the oldest stems to 24” each year in late winter to early spring. This will eliminate a top-heavy shrub that flops to the ground by midseason by providing a frame that helps to hold up new stems, and contribute to robust flowering.

Hydrangea paniculata Panicle hydrangea

Native Range: southern and eastern China, Korea, Japan and Russia

Panicle hydrangeas bloom on new growth and should be pruned in late winter to early spring before its leaves emerge. You can prune just below each flower head, basically ‘dead-heading’ the shrub. Or, because this species of hydrangea blooms on new growth, it can be pruned moderately to make the shrub smaller, or pruned severely to rejuvenate.

Hydrangea quercifolia Oakleaf hydrangea

Native Range: Southeastern part of the United States

Oakleaf hydrangeas are usually the first hydrangeas to bloom in early summer. They flower on new wood and typically do not rebloom. As a rule, oakleaf hydrangeas do not require much pruning. If you prefer to tidy it up, remove the dead flower heads just under the bloom.

Remove dead or damaged branches any time of year.

Hydrangea anomala ssp. petiolaris Climbing hydrangea

Native Range: the woodlands of Japan, the Korean peninsula, and on Sakhalin island

Climbing hydrangea is a vining species that grows up structures with aerial rootlets along its stems that allow the branches to climb. This species blooms on old wood and can be pruned in summer, after flowering. However, pruning is not required other than to remove dead or damaged stems.

Hydrangea serrata Mountain hydrangea

Native Range: mountainous regions of Korea and Japan

Mountain hydrangeas look very similar and are closely related to bigleaf hydrangeas. Flowers develop on old wood. Reblooming types are increasingly available and provide more reliable blooms.

Cut back winter-damaged stems in early spring.

VERSATILE HYDRANGEAS - Part one

Hydrangeas are vibrant, long-lived shrubs that produce varied and beautiful blooms throughout summer and into fall. They are incredibly versatile, available in a range of sizes, forms, and flower colors, they can enhance every garden. Sizes available range from ones that grow two to three feet tall and wide, while others are capable of reaching 15 to 25 feet in height with a spread of 10 to 20 feet. Hydrangea flower colors can be pink, purple, blue, red, white and shades in between. This large group of plants are easy to grow, tolerant of most soil types, grow in sun or semi-shade and require little maintenance. Hydrangeas can be planted singly or in groups, in flower beds and borders, foundation plantings, and even thrive in containers.

There are six species of hydrangeas that are commonly grown in American gardens: bigleaf (Hydrangea macrophylla), the most common; smooth (Hydrangea arborescents); panicle (Hydrangea paniculata); oakleaf (Hydrangea quercifolia); climbing (Hydrangea anomala ssp. Petiolaris); and mountain (Hydrangea serrata). Most are natives of Asia, but some are native to the United States. Each of these requires a different amount of sunlight, and has various colors and blooming times. Within these species there are hundreds of cultivars and these deciduous shrubs start blooming in summer and continue up to frost. New cultivars of hydrangeas are being introduced every year.

Characteristics -

Hydrangea macrophylla

Color: White, pink, blue, purple or red

Bloom time: June to October

Hydrangea arborescens

Color: white to pink

Bloom time: June to September

Hydrangea paniculata

Color: white to pink

Bloom time: July to September

Hydrangea quercifolia

Color: white to pink and red

Bloom time: July to September

Hydrangea anomala ssp. petiolaris

Color: white

Bloom time: May to July

Hydrangea serrata

Color: pink or blue

Bloom time: June to August

For a brief explanation on the meaning of genus and species: In the plant kingdom, genus is a taxonomic group covering more than one species. The species name relates to a sub-group of one or more plants within the genus. These plants will share similar characteristics with each other.

While answers to the number of species of the genus Hydrangea vary, worldwide there are approximately 70 species. The native range of the genus extends from southern and eastern Asia (from Japan to China, the Himalayas, and Indonesia) and North and South America.

What is the difference between a cultivar and a variety? Garden writer David Beaulieu says, “A cultivar, short for cultivated variety, is a plant that is propagated through human intervention to develop a desirable characteristic and ensure it retains the characteristics of its parent plant. A plant variety is found growing and reproducing naturally in the plant kingdom. It varies from its standard species in some way as a result of natural evolution.”

Should you prune hydrangeas? - Yes and no! Some hydrangeas flower on old wood, some on new wood, and newer cultivars flower on old and new wood (blooms on old wood, meaning the flower buds form on stems that grew the previous year). So it is important to prune them the correct way so as to not detrimentally affect their flowering. Hydrangeas that bloom on old wood, including bigleaf, oakleaf, and climbing hydrangeas, produce flower buds during the later part of the summer season. If these shrubs are pruned in the fall, winter, or spring, the buds will be removed before they get a chance to produce blooms. And the way you prune the different hydrangeas differs. There’s still more to come in the next article.

Until then, in closing - there should be a hydrangea every garden!

A FOUR-SEASON GARDEN

“In the garden, you experience birth, life and death. And that happens in our life as well. We are born, we live and we die. We can see it in a garden in — let's say, in four seasons, so you see the whole process of your own life in four seasons, and then it starts all over again.” - Piet Oudolf, world-renowned garden designer

What is a four-season garden?`

A four-season garden is a garden designed to look beautiful and interesting in every season throughout the year. While blooms are an essential part of any garden, and a lot of gardening is focused on flowers, beauty comes from more than just flowers. The gardens that provide the most pleasure are the ones with a mix of eye-catching plants in spring, summer, fall and winter.

How do you design a four-season garden?

The plants should include a combination of qualities, such as shape, color, form, and texture, with a focus on foliage, flowers, fruit, berries, and bark. Artistic arrangements can be created using these garden design principles. Consider your landscape as a community of plants rather than individual plants. Piet Oudolf explains, “If you have beautiful plants, it doesn’t mean your garden is beautiful. Something is complete when everything works together.”

Within these plant communities, think about designing in layers from ground cover plants to the canopy trees, with bulbs, grasses, perennials, and shrubs in between. Layering plants with a variety of heights, while choosing some plants for winter interest; a four- season garden can be beautiful during the winter months.

What does winter interest mean for plants?   

The most obvious winter-interest plants are evergreens. Evergreens can be trees or shrubs and can be needle evergreens, like pines or spruces, or those with “broad leaves”, like boxwood, rhododendrons, and hollies.

Beyond evergreens, there are trees and shrubs with ornamental bark or attractive branching structure that is revealed after they lose their leaves. Some have colorful branches and stems.

There are types of perennials and ornamental grasses that are semi-evergreen and others that remain through the winter and offer architectural interest, and a habitat for the birds.

Another decorative feature can be seed heads or seedpods, cones, or dried flowers on trees, shrubs, and perennials.

Plan to cut back these and ornamental grasses in early spring instead of fall.

Some trees and shrubs feature fruits or berries in late summer or fall, which persist into winter. There is a wide range of berry- and fruit-bearing woody plants with colors such as crimson and red, orange, yellow or gold, blue, purple, and black.

Plants with seeds, cones, or berries will attract birds and other wildlife species.

A well-balanced garden design -

In a well-balanced garden design you will have spring-flowering bulbs, perennials, shrubs and trees, followed by summer and fall blooming plants.

◆“Shop for plants in spring and throughout the year. If you shop only in the spring, you will be attracted to those plants in bloom at that time, and you will miss buying for all four seasons,” Edward Lyon, horticulturist at Iowa State University recommends.

◆Design for a succession of blooms and choose long blooming perennials. Spring bulbs will be purchased and planted in fall. Trees, shrubs, perennials, and ornamental grasses can be planted in spring, summer, and fall.

◆Plan your four-season garden so it creates interest whether it’s viewed from inside or outside.

◆Visit public gardens, not just garden centers. Both are great for learning about plants and getting ideas. Visit these in different seasons, too.

◆With research and planning, your garden can become a four-season garden of ever-changing beauty.

HURRAH FOR HELLEBORES - the perfect perennial

While most perennials lose their foliage in the fall and go dormant in the winter, there are those, like hellebores that are evergreen. With flowers that blossom in late winter and early spring, cold-season bloomers like these are rare in the flower world. At times the leaves are flattened and flowers droop due to winter frost and snowfall, but before long, they recover when the warmth of the winter sun reappears.

  Folklore dating back to Greek antiquity, and found throughout history, tell of the magical and medicinal qualities of hellebores. Its black roots were known for centuries as a cure for mania and melancholy. Hellebores are said to have the ability to ward off evil spirits, and it’s considered a sensible precaution to plant it as close as possible to the entrance of the home. Ironically, in witchcraft it is believed to be used for summoning demons.

  Hellebores were brought to North America for ornamental use in our gardens around 1850. They are valued for their early and long-lasting flowering period, as well as for their beauty, vigor and deer resistance. Until about 30 years ago, these perennials were uncommon in home gardens.

  Commonly known as hellebores, the genus Helleborus consists of approximately 20 species of evergreen perennial flowering plants. Most of the hellebores readily available today are hybrid crosses of nine species, collectively referred to as Helleborus x hybridus. Mature plants form clumps that are 18” to 24” tall and 24” to 30” wide.

  Native to much of Europe, hellebores (Helleborus) belong to the Ranunculaceae or buttercup family. Like most members of the buttercup family, hellebores are avoided by deer because their leaves, stems, and roots are poisonous.

Leaves - Even when hellebores aren't in flower, their foliage is attractive too. The leaves are palmate with serrated edges and come in different shapes depending on the variety. The leafy stems grow from the base of the plant and are topped with five to nine leaflets. New leaves are smooth initially and turn leathery as they age. Hellebore foliage is glossy and durable and is typically dark green, although there are continually new hybrids with variations of leaf color such as gray-green, blue-green, pewter, and there are others with colorful veins of red, white, silver or mottling. Although the foliage is evergreen, the leaves decline as winter progresses.

Flowers - Hellebores have saucer-shaped flowers, two to three inches in diameter appearing on thick stems that rise above the foliage. There are hybrids in a wide variety of colors which can be pink, yellow, white, cream, green, maroon, or purple. They come in single, semi, and fully double forms, with ruffled or smooth petals. Some varieties have colorful veins or margins, others are spotted or speckled. The blooms on most of the older varieties are downward-facing, but the newer hybrids have more upward-facing flowers.

Growing conditions - Hellebores grow best in well-drained soil, rich in organic matter, but tolerate most growing conditions, with the exceptions of very dry or wet soil. Most prefer partial shade, but some varieties will tolerate sun. While they are mostly thought of as “shade plants,” they are in fact shade-tolerant plants.

  Clumps of hellebores blooming in February or March are a joyful experience to behold. Locate plants to enhance views out of windows or near walkways so that the early blooms may be savored. Group plants in semi-shady locations under trees or large shrubs, woodland gardens or border fronts. When flower stems are left in place, many hellebore hybrids will spread by self-seeding and form an attractive ground cover.

How to care for hellebores - Hellebores require little maintenance, except for cutting back winter-damaged leaves in late winter or early spring. Allow the healthy evergreen foliage to remain on the plant throughout winter. New leaves appear in the spring. Dead or diseased leaves can be pruned at any time of year. Cut leaves back to the base of the plant. Use hand pruners, and wear gloves when handling this plant as the sap of the hellebore can irritate the skin. There is no need to rush in removing the faded flower stems. The flower heads will last through most of the summer and continue to offer ornamental interest in the garden. The showy flower parts are not petals, they are sepals; the sepals remain attached to the plant until late in the season. Cut back flowers by removing the entire stem at the base.

Companion plants for hellebores - Plants that require the same growing conditions:  a wide range of partial sun to shade tolerant perennials, ferns, sedges, grasses, and shrubs. Also include bulbs that bloom at the same time as hellebores.

  There are many hellebore species, cultivars, and hybrids to choose from. With a well-planned selection, you can have hellebore flowers in your garden from January to June. No garden should be without hellebores.

PROPER MULCHING TECHNIQUES ARE THE ROOT TO HEALTHY TREES

Proper mulching techniques are the root to healthy  trees -

“Mulch volcanoes" are extremely harmful to the health of trees. Over-mulching in the shape of a mound around the trunk of the tree is pejoratively referred to as a mulch volcano. Mulch is piled up so high that the trunk flare is buried. The trunk flare is the base of the tree which tapers out just above where the root system begins. A buried trunk flare will lead to disease, decay, root rot and the eventual death of the tree. Over-mulching is a pervasive occurance and painful sight to knowledgeable professionals who see the practice as killing trees with kindness.

The phenomenon of over-mulching began with the intention to prevent mowers and trimmers from damaging tree trunks. Unfortunately, over time, homeowners and landscapers believed that if adding a layer of mulch around the base of a tree was helpful, then a pile of mulch must be even better. When homeowners see landscape professionals adding mulch piled high directly against the trunk of trees, they presume that is the correct method. Landscapers see other professionals mulch this way and think it is the correct way to mulch. And seeing mulch volcanoes everywhere has furthered the misconception that this is the proper way to mulch.

Why mulch volcanoes are bad - Trees with too much mulch around the base of the trunk experience a wide variety of stress. Trees need to breathe. They need oxygen to survive and when buried in mulch, they can’t breathe properly. Roots may grow upward, out of the ground, and into the mulch searching for water and oxygen. Piling mulch against the trunk holds in moisture which can cause the bark to rot. The side effects of over-mulching occur slowly and a tree’s decline will likely be blamed on other problems. Because it is a slow death, there is usually not an associated link. As a tree declines in health, its immune system is weakened, and it becomes more susceptible to attack from insects, diseases, and harmful fungi.

How to repair an over-mulched tree - Remove excess mulch and soil until you expose the flare of the tree. Use a shovel or garden fork, and then rake, being careful not to damage the bark of the tree. If there are roots growing into the mulch, use pruning shears and remove those roots carefully. These are called adventitious roots. Their development can be in response to adverse environmental conditions or stresses, and as they grow in diameter, they can develop into girdling roots. Lastly,  after breaking up any clumps, reapply mulch around the tree to a depth of two to four inches, making sure there is no mulch within four to six inches of the base of the tree.

How to apply mulch - Organic mulch is recommended, meaning mulch that comes from plants as opposed to inorganic mulches such as gravel or decorative rocks. Organic mulch choices can be leaves, bark, pine needles, cocoa shells or wood chips.   

Fresh mulch can go on top of old mulch, but loosen the existing layer first if it’s matted down or crusted to improve drainage and air movement.

Apply the mulch around the tree to a depth of two to four inches, making sure there is no mulch within four to six inches of the base of the tree. The mulch should be spread out almost flat. All of this applies for shrubs and perennials as well.

Why mulch can be beneficial - Mulch conserves soil moisture, moderates soil temperature, reduces growth of weeds, helps protect soil from erosion, prevents frost heaving in winter and adds organic matter to the soil as it breaks down. Mulch makes garden beds and landscapes look more tidy and attractive.

Proper mulching techniques are the root to healthy trees.

LICHENS: ROCK STARS THAT NEVER HAD A NUMBER ONE HIT

All of the world's animals, plants, fungi and microbes are connected. Being curious about nature can inspire you to explore the wonders of the natural world. Have you ever taken a close look at lichen? Lichens are all around us and are mostly ignored. But if you tune in to your surroundings, perhaps you will begin to become aware of lichens on rocks, tree bark, soil, gravestones, wood benches, roofs, or fences. Lichens can also grow on glass, metal, plastic and cloth. Lichens are living organisms. Although it looks like a plant, it’s not. In order to survive, lichens need water, light, air, nutrients, and a surface on which it can grow. They get water from rain and fog, and absorb water vapor from the air.

What are lichens?

Until the use of microscopes revealed otherwise, lichens were once classified as single organisms. Magnification showed lichens were two organisms living together in symbiosis: a fungus and an algae. The word symbiosis was invented to describe lichen. The fungus provides support, water, and minerals for the algae, while the algae photosynthesizes, producing food for the fungus.

In recent studies it has become evident that while lichens contain at least two different kinds of life made up of organisms belonging to different kingdoms, they are also ecosystems for many other microorganisms, such as bacteria, yeast, and additional algae and fungi. Lichens are now understood as a community of organisms rather than a simple fungi-algae association.

Appearance:

Lichens come in different forms, colors, and sizes.

There are four main lichen body types: crustose (crusty), fruticose (shrubby), foliose (leafy), and squamulose (scaly).

Lichens can range in color from grey, green, black, white, yellow, orange or red, and almost everything in between. Individual lichens often form mosaics of color.

When dry, lichens appear dull-colored, the color of the fungus. But when wet they are completely transformed when the colors of the algae layers shine like superstars.

Lichens range in size from as small as a shirt button to strands that can be several feet in length.

Lichen habitat:

Lichens are everywhere throughout the world. They are the dominant form of life on about 8 percent of the earth’s surface. Lichens grow in temperate, tropical, and polar regions. They survive in some of the most extreme environments on earth: arctic tundra, high mountain peaks, deserts, and rocky coasts. Lichens can survive a complete loss of water, become dormant, and then rehydrate when water becomes available. To ensure survival, “Lichens produce an arsenal of more than 500 unique biochemical compounds that serve to control light exposure, repel herbivores, kill attacking microbes, and discourage competition from plants," according to the Lichens of North America site.

Uses:

Lichens provide forage, shelter, and building materials for deer and other large animals, as well as birds, rodents, and insects, as described by the USDA Forest Service.

Lichens are used in deodorant, toothpaste, ointments, extracts, perfumes, and dyes for fabric. Some species of lichens are also thought to have medicinal properties.

• Are lichens on trees harmful?

Tree-dwelling lichens are not harmful to trees. They are often mistaken for destructive fungi or diseases, but they are not pathogens or parasites, and do not cause disease. Lichens attach to trees but do not feed off the bark. They produce their own food using sunlight energy (photosynthesis).

On a final note, lichens are a partnership between organisms unlike any other organism on earth. They are all around us and we hardly notice them.

BOXWOOD: A CELEBRATED SHRUB

Boxwood has been used since antiquity in gardens throughout the world. It has long been valued for its permanence in the landscape, extremely hard wood, and its medicinal value. This is a long-lived plant, many specimens living considerably more than 100 years.

  Boxwoods are native to western and southern Europe, and portions of Asia, Africa, South America, Central America, and the Caribbean. There are no boxwoods native to North America. Boxwood is the common name for the genus Buxus, and a family relative of Pachysandra.

  Although there are about 90 species of boxwood, just three of them, and their hybrids, make up the majority of boxwood used in landscapes in the United States today. Boxwood was introduced to North America from Europe in the mid-1600’s. According to The American Boxwood Society, the first planting was around 1653 at Sylvester Manor on Shelter Island, New York, using boxwood brought over from Amsterdam.

  Boxwood has a history immersed in myths and truth: these plants were in use among the Egyptians, Greeks and Romans. To the Greeks, boxwood signified strength. Boxwood sprigs have been found in the tombs of Romans. To dream of boxwood was said to foretell long life. Boxwood is one of the few woods heavier than water, and is used for carving, making woodcuts, and constructing precision instruments. Traditionally used in formal gardens, most commonly for hedging, topiaries, and containers, boxwood is an excellent choice for edging, screening and mass foundation plantings. Boxwood cultivar choices offer a variety of shapes, including rounded, columnar, upright, pyramidal or spreading, with sizes ranging from 1-20 feet tall and 2-8 feet wide.

  Deer do not browse boxwood due to distasteful or poisonous alkaloids in the leaves. It is one of the few evergreen shrubs that is usually not damaged by deer and a reason for its widespread use in our area. Unfortunately, when a single plant variety is overused, it becomes vulnerable to disease and insect pests. In reference to a study by the University of California, entomologist William Wetzel said, "A monoculture is like a buffet for plant-eating insects where every dish is delicious.” And a delicious buffet for pathogens, as well.

  “Winter burn” is a common problem of evergreens, including those with “broad leaves”, like boxwood. Leaves do not actually burn but rather dry up. Leaves turn yellow or brown in response to low soil moisture, freezing temperatures and blowing wind. Nurturing healthy boxwood is the best way to protect against insect, disease or winter damage, and in spite of these potential problems, boxwood remain a popular and easy to grow shrub.

Cultural Practices for Boxwood Health    

Light requirements: Boxwood will grow in full sun, but many prefer part shade.

Moisture: Moist, well-drained soil is best. Boxwood do not like wet feet and are highly susceptible to root rot. Once established, they’re drought tolerant and only need water after an extended period of time with no rain.

Mulching: Boxwood are shallow-rooted and benefit from a thin layer of mulch to protect the roots. A thick layer of mulch should be avoided as it may encourage roots to grow above the soil surface, putting them at risk of damage when dried out.

Shearing, pruning and thinning:  A common belief is that it is mandatory for boxwood to be drastically sheared into balls and flat-topped hedges for optimum maintenance. This is actually incorrect. Shearing encourages leaf growth only at the ends of branches, and over time, continual shearing transforms boxwood into a shell of outer leaves with a dead center. With every shearing each branch becomes four to six new branches. This occurs because the apical (dominant) buds have been eliminated, causing plant hormones to inhibit the buds below from growing. Because sunlight and air can’t reach the interior, the plant becomes susceptible to disease. Boxwood should have a green interior, with leaves all the way up the branches. Minimal shearing (no more than once a year) is essential to a healthy boxwood.                                                                                                           

  Why prune? For aesthetics and health. Boxwood can be pruned by hand to shape them to improve the overall appearance. Branches that are too long can be cut back from inside the shrub. This is “selective pruning”, as opposed to “shearing”, which is non-selective. When shaping, taper them so that the bottom is broader than the top, to ensure the entire plant will be exposed to sunlight.

Prune dead branches, remove any debris or fallen leaves from the interior, and thin the plant by removing some of the branches from the center of the plant. Thinning and cleanup allows sunlight and air to reach the interior of the plant which promotes new growth, helps to prevent disease, and increases the longevity of boxwood.

To learn more:

www.boxwoodsociety.org/abs_care

www.saundersbrothers.com/_ccLib/attachments/pages/Boxwood+Guide+copy.pdf