Fall Cleanup Q and A
Cutting Back Perennials
Question: After the first frost, should I cut back the flower stalks on my perennials? Or is it best to leave them as is and cut them back in the spring?
Answer: If winter temperatures in your region are regularly below 0 degrees F, don't cut back the perennials until late winter or early spring. The dead foliage helps protect the plants from cold. After the ground freezes, cover the whole bed with a loose layer of straw. Leave it until early spring and then gradually remove it as temperatures warm.
Pruning Ornamental Grasses
Question: What is the proper method of cutting back ornamental grasses for the winter?
Answer: Most gardeners wait until after the grasses have bloomed so that they can enjoy the ornamental plumes. The seedheads are also attractive in winter, so you may want to wait until spring to trim them. Then, cut the dead grasses back to about 6 inches; the new growth will quickly cover the old stubs. Some gardeners use a hedge trimmer, as this is much faster than using a hand clipper.
Question: I would like to make a 4x4x4 fenced-in area and compost fall leaves. If I fill the bin in early November, will the leaves decay by the middle of May, when I can rototill them into the soil?
Answer: Composting essentially stops when the weather turns cold, and plain fallen leaves alone can take a year or more to decompose. To speed up the process, shred the leaves with your lawn mower, then till them into the soil this fall. By spring they should be decayed enough for planting.