Why Planting in the Fall is Good
Every now and then, a friend will ask me about the best time to plant shrubs and trees. They are usually surprised to hear me answer, “Nearly anytime, but especially in the fall.” Fall is a great time to plant almost any kind of plant.
But why is it good? Isn’t spring better? To answer that, you have to understand how a plant grows. Whether we are talking about seeds, transplants or trees, the roots always start growing before the shoots. Planting while the soil is still warm allows the roots to gain a foothold and become established before winter. Plant growth ceases as the weather gets colder and since the air temperatures cool down before the soil, the top growth naturally stops growing before the roots. Since most roots continue growing until the soil temperature around them reaches 40 degrees, your plants gain a distinct advantage for the spring.
Not to say that spring planting is bad, it isn’t. Lots of plants go into the ground in the spring and do just fine. But coming out of winter the soil is cold and warms more slowly than the air, so the roots get started slowly. An established plant with a sturdy root system will be able to grow more quickly than one newly planted.
Another reason to plant in the fall is related to heat stress, or actually, the lack of it. The blistering heat of summer has subsided so both you and your plants benefit. You won’t get heat stroke from digging holes and the plants won’t be heat stressed. Less stress means better growth.
Wow, does fall planting give your plants an advantage or what? Not only are your trees and shrubs already acclimated and more stable, but should be established enough to produce strong new top growth, leaves and lots of flowers in the spring.
A Few Things to Remember About Planting in the Fall.
Do water your plants until they become established. The same rules apply - water deeply once a week until the ground freezes. It would be terrible to give your plants all the advantages of fall only to lose them because of water stress. Winters in our area are generally dry so don’t forget to check them through the cold months and water if needed.
Don’t fertilize your plants when planting in the fall. Too much nitrogen can cause excessive top growth, which will not have a chance to harden before freezing. Damaged and frozen top growth provides excellent entry points for bacterial and fungal diseases. You really don’t want that.
Do wait to trim your plants. Trimming too soon could cause a flush, which might not harden off before the freeze. Or you could be trimming off next spring’s flowers. In other words, know your plants and when you can safely trim them. Don’t trim plants like lilacs and certain Hydrangea varieties until after they have bloomed or you will have to wait another year for those glorious blossoms. On the other hand, trimming some plants when they are dormant allows more early branching, ultimately creating a fuller plant.
Don’t plant too late. You want to give your plants’ roots time to grow and become established before the ground gets too cold. Besides that, frozen ground is really hard to dig. You can help protect the roots from cold and moisture loss with a well-applied layer of mulch. However, remember that you want a mulch “donut” rather than a mulch “volcano.”
Do take time to enjoy the results of your labor. Otherwise, what’s the point?