Come autumn, we think about cleaning up our garden beds and getting ready for winter. The average first “killing” frost date in our area is 11/8 – 11/28. Although it may not seem intuitive, it is best to wait until after the first hard frost to put down a 3” layer of mulch. Use wood chips, pine needles, compost or ground leaves around your trees, shrubs and perennials. This layer will act as winter protection and an organic fertilizer to spur spring growth. Using ground leaves in your gardens saves our landfills and provides benefits to the soil. Although raking and hauling seem onerous, gathering the leaves into one area and running over them with your lawnmower is one way to make the task easier. You can also blow the leaves into a garden corner and let them naturally break down, which will produce the great soil conditioner called leaf mold (or mould).
Perennial beds can be trimmed this time of year. This includes cutting back the stems and foliage and removing the debris. But you may want to rethink this task. Insects, including beneficial, may find winter homes in the stems and foliage of Coneflower (Echinacea), Black-eyed Susan (Rudbeckia hirta) and other hollow stemmed perennials. Other plants may still have seed heads to feed the birds. Trim these plants in early spring, before new growth begins. A pile of brush or a woodpile in a sunny area may provide a safe spot for butterflies, such as the hackberry, mourning cloak and red admiral that overwinter as adult butterflies.
Ornamental grasses will provide winter interest in the garden and can be trimmed in late winter before new growth begins.
Vegetable gardens should be cleared of spent plants and debris. Don’t compost this material if there has been evidence of disease or insect infestation. It can be burned, as permitted, or taken to the trash facility. Spread a layer of compost or ground leaves on the vegetable beds, or plant a cover crop to protect bare soil. Some fall crops, including carrots, radishes, leeks, onions and beets can remain in the ground even after first frost. A light frost improves the sweetness of leafy greens and root crops. However, when the temperature drops below 25F, you will need a cover to retain these vegetables.
After leaf fall, look at your trees and shrubs and prune any broken limbs or crossing branches to prevent damage during winter storms and winds. Pruning for shape and style can be done toward the end of winter or early spring.
Go to Virginia Cooperative Extension website at www.ext.vt.edu for additional information or contact the Master Gardeners Help Desk at 804-580-5694. If a question cannot be asked during office hours, the Master Gardeners can be contacted by email at email@example.com. Please state the question with as much detail as possible along with contact information and it will be routed to a Help Desk or Master Gardener expert.
By CarolAnne Taylor
Virginia Master Gardeners are volunteer educators who work within their communities to encourage and promote environmentally sound horticulture practices through sustainable landscape management education and training. As an educational program of Virginia Cooperative Extension, VMG’s bring the resources of Virginia’s land-grant universities, Virginia Tech and Virginia State University, to the people of the commonwealth.