Lee Miller is a professional landscape designer, garden blogger and author involved in the horticultural industry since 1996. Having started a gardening blog in 2010, she has written over 250 articles on general gardening, landscape design principles, gardening tips, planting, pruning, garden maintenance, feature plants and more. In addition, Lee Miller is the author of two books, A Guide to Northeastern Gardening, published in 2015 and Landscape Design Combinations, published in 2017. Lee enjoys sharing her experience with others and with trowel in hand since the age of five, her passion for gardening continues to grow.
It’s time to think spring and begin getting the garden ready for a successful start to the planting season. Getting a good start on spring garden maintenance will allow you to reap the rewards of a thriving garden during the warmer days ahead. Here is a list of recommended gardening tasks to be performed in late winter/early spring to get you into the gardening frame of mind and start the season off right!
PREPARATION OF GARDEN BEDS
Proper preparation of garden beds is essential in getting a good start to the gardening season ahead. If you have left annuals or perennials for winter interest, now is the time to tend to them, along with any weeds that might have survived the winter. Pull out any dead annuals and prune perennials back to the ground to encourage new growth once the threat of frost is gone and nighttime temperatures are in the 50’s. If cold temperatures are still to be expected, push mulch up around the crown of the plants to protect them from temperature fluctuations and concentrate on removing weeds to stay proactive.
Mulching is a good practice in keeping plants healthy and reduces landscape maintenance. A good organic mulch helps to conserve about 10 to 25 percent of the moisture lost from plants through evaporation, keeps the soil well aerated by reducing soil compaction and releases beneficial nutrients and organic matter. Mulch serves its function best at a depth of 2-4 inches and should be kept 1 to 2 inches from the base of plants to prevent bark decay. Depth of mulching can vary depending on the type of material used and the drainage conditions of the soil. Sandy soils tend to dry out quickly and often benefit from a slightly deeper mulch layer (3 to 4 inches), while a very moist area may not benefit from mulching at all. Mulch acts as an insulator and should be applied in spring after the ground thaws. Applying beforehand could possibly inhibit natural warming of the soil, so wait until all danger of frost is gone.
WHEN TO PRUNE FLOWERING TREES & SHRUBS
General rule of thumb is to prune flowering plants AFTER they flower. Early spring flowering trees and shrubs including rhododendron, azalea, forthysia, magnolia, plum, Eastern Redbud and cherry form their buds from the season before and should be not be pruned until after flowering. Pruning them now will remove flower buds that have already formed, resulting in a loss of blooms.
Summer flowering shrubs such as Spirea and Buddleia (butterfly bush) prefer a spring pruning to promote fullness and blooms. Prune Spirea slightly for shaping. If the plant is overgrown to the point it is unsightly, it can be pruned more drastically to rejuvenate it now in spring. Buddleia benefits from an early spring pruning and should be pruned all the way back in late winter/early spring to promote fuller plants and better blooms in late summer. This practice is best performed once you see signs of life on your plants.
PRUNING OF EVERGREENS
Most evergreens can be pruned anytime when there is no threat of extreme temperature changes that would cause undue stress; however, the best time is either in early spring before they push out new growth, or afterwards once new candles form. Ideally the best time to prune evergreens is believed to be in March (late winter or early spring) before new growth starts. This also eliminates any winter burn that can occur during especially cold weather and gives the evergreen a good start for Spring. Your flowering evergreens are an exception to this rule and should not be pruned until after blooming (late spring). When pruning evergreens that form candles, such as white pine, it is best to cut candles in half to keep the plant more compact.
PRUNING ORNAMENTAL GRASSES AND TENDER PERENNIALS
Spring is the time to prune back your tender perennials, such as ornamental grasses and liriope. These perennials can be cold sensitive and exposing the crown of the plant in wintertime can lead to snow and cold damage, causing the centers to “hollow out”. It is best practice to leave spent foliage remaining for winter interest in the landscape, while providing protection for the plants over the colder months. When winter is though, prune the plants back in spring to allow for new growth to emerge. Spring is also the time to divide and move other perennials that have become overgrown. It is recommended that most perennials be divided every four years for best bloom. Dig up and divide with a sharp clean spade just as new growth appears, replant and add a sprinkle of slow release plant food in with the soil to help root promotion. Water in thoroughly.
After wintertime is a good time to do some proactive maintenance on your roses. Wait until all threats of frost are over and your roses are sprouting new shoots and showing signs of life. Then, prune off dead wood or overgrown branches back about one third the size of the plant to promote strong new growth and blooms. Be careful to watch while pruning so that you achieve a nice rounded shape for your plant. Early spring is also a good time to apply an organic slow release rose fertilizer mixed in with the soil at the base of the plant to ensure a successful start to the growing season. I would also recommend a regular watering schedule from the base of the plant, since roses do not fare well with constant water on their foliage.
PLANT SUMMER BLOOMING BULBS
While spring blooming bulbs such as crocus, hyacinths, tulips and daffodils are planted in fall, late summer blooming bulbs or tuberous roots such as Dahlia, Canna and Gladiolus are planted in spring. Once the threat of frost is gone, dig a hole twice the size of the bulb and amend the soil with compost or manure to ensure plants a good start. Generally, bulbs or tuberous roots should be planted at a depth of three times their diameter in a well-drained soil. Larger sized plants are generally planted at approximately eight inches apart while smaller sizes at four inches or less. While many bulbs prefer to be planted in a slightly acidic, well-drained soil in full sun, specific requirements vary according to each individual plant and are readily available on packaging. Once planted, water your bulbs thoroughly and keep watered regularly to keep moist (but not wet) while allowing soil to dry slightly between watering.to prevent rotting. Applying bone meal at time of planting will give your bulbs energy during the growing season, but do not mix in too closely to the roots.
POST WINTER CARE OF EVERGREENS
Winter bronzing and winter burn are two phenomena resulting from winter dryness and wind. Winter bronzing (photo left) is normal on some evergreens (such as some species of Arborvitae and Cryptomeria) near the end of winter while seasons are changing. Once the temperatures rise and new growth is stimulated, the foliage should turn back to a more vibrant green. Broken or dead branches are different in that they are completely dried out and brown. These should be pruned off the tree in late winter/early springtime to prevent any further damage. Split branches can be arbor tied together, and if caught in time the cambium growing layer of the tree can mend.
Browning of the needles or “winter burn” (photo right) results from harsh winter winds and should correct itself once the weather starts to warm and water is able to get to the cells of the plant, activating the chlorophyll within. If the tree is well established, it should most likely fully recover and start to push out new growth as the temperatures rise. If the tree looks severely damaged, getting water to the roots and deep root feeding in early spring are recommended to help the plant to recover. Deep root feeding is a controlled fertilization process that supplies immediate beneficial nutrients directly to the root system to give it a boost. There are also products on the market which contain micro nutrients and beneficial bacteria to help the roots to absorb nutrients and help plants in stress. NOTE: It is a normal process of evergreens to shed their inner (older) needles or foliage in the Fall/Spring to allow for new growth.
UNPREDICTABLE WEATHER AND THE GARDEN
I have had numerous inquiries over the past couple of years from clients concerned about erratic weather conditions and plant vitality. Generally, plants are resilient. Buds that are forming on the trees early are sparked by warmer temperatures but slowed down when the temperatures drop, which tends to balance out their progress. If there is severe cold for a prolonged time, buds could freeze and suffer damage, but fortunately most trees produce enough buds to still produce a bloom. Some plants such as ‘Endless Summer’ and ‘Pee Gee’ Hydrangea bloom on the new wood of the season and should weather just fine. More sensitive plants like old fashioned hydrangea ‘Nikko Blue’ that bloom on old wood are more susceptible to cold, and time will tell. If there is die back on your plant, prune out the dead wood and apply a dose of a high phosphorus fertilizer. It could help to boost larger blooms from any undamaged buds and help your plant to look its best.