Leaf color varies depending on timing, weather

Published 12:00 am Thursday, October 27, 2011

By Darrell Blackwelder
For the Salisbury Post
SALISBURY — The unusually warm weather earlier this month has provided many the opportunity to continue working outdoors. Cooler, wet weather on the horizon may slow our endeavors, but there are still questions about landscape maintenance. Below are a few questions received over the past few weeks.
Q: My maple trees seem to have better leaf color this year. Why is leaf color more pronounced some years?
A: Fall leaf color, especially red, depends much on warm days and cool nights during the fall. As the days’ length begins to shorten, chlorophyll is gradually reduced, allowing color pigments to show through the leaves. Yellow colored leaves generally retain the same colors each year. Trees with red leaves are greatly affected by weather, especially in the fall.
Q: Can I still fertilize and seed my lawn now?
A: Yes, but germination will be slow with the cooler weather. Be sure to keep falling leaves off newly emerging grass seeds.
Q: Is now the best time to cut back trees and shrubs? I have some older hollies that need to be severely pruned.
A: It’s best to wait until mid-March to heavily prune evergreen shrubs. Our weather has been too variable and the chance of a late freeze is always a problem. Spring blooming plants such as azaleas and camellia japonica should be pruned after bloom in the spring. Buds are set in the fall and pruning now removes much of the flowers for spring. This is also true for other spring flowering trees and shrubs. However, trees and shrubs can be lightly pruned now. Excessive summer growth, water sprouts or an occasional limb that hampers mowing can be removed without major damage to the plant
Q: Can I still plant pansies?
A: Pansies can still be planted. Make sure that the plant beds are deeply tilled with ample soil amendments. Mulch newly set plants with a layer of fine bark. Dead head spent blooms throughout the fall and winter to allow maximum root growth. Fertilize with a water soluble fertilizer when temperatures fall below 60 degrees. Try to avoid fertilization during unseasonably warm temperatures; warm temperatures cause pansy plants to stretch and become weak.
Darrell Blackwelder is the County Extension Director with horticulture responsibilities with the North Carolina Cooperative Extension Service in Rowan County. Learn more about Cooperative Extension events and activities by calling 704-216-8970, Facebook or online at www.rowanextension.com