CHARLESTON, W.Va. -- As the gardening year rolls to a stop, it is time to think about preparing trees and shrubs for their winter sleep so they'll awaken refreshed and ready to get to business once the blush of spring calls them to attention.
It may sound silly to say that now is the time to concentrate on caring for trees and shrubs, when they are getting ready to go into their winter dormancy. But what we don't often realize or see is that the trees are never fully asleep in the winter. Plus, some basic care now will help avoid winter damage that can kill branches and deaden entire areas on some shrubs.
Fertilize in the fall
While trees and shrubs may lose their leaves or stop growing aboveground for winter, the roots are still growing beneath the soil and pulling up water and nutrients when the soil isn't frozen. They take the focus away from the top of the plant, and instead take a little time to rebuild and replenish. It's almost like a tree meditation retreat. To facilitate this growth, the fall is the time to fertilize trees so that they have a sufficient amount of nutrients available as building blocks.
Root growth is particularly encouraged by the presence of phosphorous, the second number in the "big three" N-P-K ingredients you'll find on the bag of fertilizer. Potassium (the K at the end of that list) also plays a part in overall plant growth. Nitrogen, which is listed first, can be applied in the fall, but it directs growth of the leafy, green parts of plants and at least some should be applied in the spring.
To quote my friend and colleague Chuck Talbott, the extension agent in Putnam County, when you talk about the N, P and K on the fertilizer bag, remember the phrase "up, down and all around."
What and how to fertilize