Have the temperatures been rising and are you yearning to go out into the garden? Spring is here and it is a time to start planning and prepping the garden for a successful start to the planting season. There are some recommended maintenance tips for getting your garden underway. Here is a list of common gardening tasks to be performed in late winter/early spring. (I recently posted this article on my other blog A Guide to Northeastern Gardening, but felt it was also fitting for here.)
Mulching Garden Beds
True or False? New mulching should be applied now before the ground thaws. False. Mulch acts as an insulator and applying mulch before thawing would actually inhibit warming as temperatures rise. Allow the soil to warm, then apply two to four inches of natural pine mulch. When applying, keep mulch several inches away from tree and shrub trunks to prevent oxygen loss and rotting. Mulch benefits plants by reducing water evaporation, preventing weeds, adding organic matter to the soil and also acts as a buffer, preventing drastic changes in soil temperatures.
True or False? Nitrogen based lawn fertilizer can only be applied after April 1st. True. According to the EPA, the prohibition on application of fertilizer between December 1st and April 1st applies to products that contain nitrogen (N), phosphorus (P), or potassium (K). If a product does not contain any of these nutrients, it could be applied during the winter months without violating this law. Explanation: If the ground is frozen, there is a greater danger of runoff and possible contamination of groundwater. Fertilizers applied when the ground is thawed and porous are absorbed and utilized by plant material and go through a natural filtration process before reaching the aquifer system. Please note that there are a variety of organic, natural fertilizers on the market that are more environmentally friendly. Success rate depends on brand and application.
Pruning Flowering Trees and Shrubs (Photo: Magnolia Royal Star)
True or False? Spring flowering trees and shrubs should be pruned in late winter/early spring. False. 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.
Pruning Summer Flowering Shrubs (Photo: Buddleia ‘Lo & Behold Blue Chip’ Dwarf Butterfly Bush)
True or False? Summer blooming shrubs such as Spirea and Buddleia should be pruned in spring. True. Mid and late 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 Evergreens (Photo: Weeping White Pine)
True or False? The best time to prune evergreens is in early spring. True. 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. 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 Liriope (Photo: Left-Ornamental Grass ‘Yaku Jima’ and Right-Variegated Liriope)
True or False? Liriope and grasses should be cut back and divided now in spring. True. Liriope and ornamental grasses can be cold sensitive. Exposing the crown of the plant could be the reason for snow and cold damage. It is best to leave liriope and grasses alone in fall and to prune them back in early spring to allow for new growth. 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.
Pruning Roses (Photo: Double Knock Out Rose Pink)
True or False? Knock Out Roses should be pruned back in early spring. True. Wait until your roses are sprouting new shoots and showing some signs of life. Then, prune off dead wood or overgrown branches back about one third the size of the plant to promote strong 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 fair well with constant water on their foliage.
Planting Summer Blooming Bulbs (Photo: Dahlia ‘Snowball’)
True or False? Summer blooming bulbs should be planted in late spring. True. While spring blooming bulbs such as crocus, hyacinths, tulips and daffodils are planted in fall, late summer blooming bulbs such as Dahlia, Canna and Gladiolus are planted in spring. Amend the soil with compost or manure to insure them a good start and plant in a well-drained area to prevent rotting. Generally, bulbs are planted at a depth of three times their diameter, and specific instructions are usually supplied on the packaging. Once planted, water your bulbs thoroughly and be sure they get watered regularly. Applying bone meal will give your bulbs energy during the growing season, but do not mix in too closely to the roots.
Endless Summer Hydrangea
Will the unpredictable weather we have been having across most of the U.S. and other areas harm my garden? I have been getting asked this question quite a bit over the past couple of years. Generally, plants are pretty resilient. Buds that are forming on the trees early are sparked by the warmer temperatures in daytime but slowed down by the colder nighttime temperatures, which tends to balance out their progress. If there is severe cold for a prolonged period of time, buds could freeze and get damaged, but the tree produces enough buds to still have a bloom. 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. Hydrangea varieties that bloom on new wood, such as ‘Endless Summer’ and ‘Pee Gee’ should winter alright.
Winter Bronzing of Evergreens
Some of my evergreens are a bronze color. Should I be concerned? Winter bronzing is normal on evergreens near the end of winter while temperatures are cold. Once the temperatures rise and new growth is stimulated, the foliage will turn back to a more vibrant green. Broken or dead branches are different in that they are completely dried out and brown. Those branches should be pruned off the tree in late winter/early springtime to prevent any further damage. Any falling or divided tree leads can be arbor tied to secure them and encourage upright growth. Split branches can also be arbor tied together, and if caught in time the cambium growing layer of the tree can mend. In the photograph above, the center upright Western Arborvitae are displaying bronzing and there are no signs of broken branches. As you can see the trees are healthy.