FLORIDA — Autumn officially begins on Thursday, September 22 this year, and it is an excellent time of year to plant shrubs and trees.
Trees and shrubs grown in containers can be planted at any time. But when planted in spring or summer, they often have to struggle to absorb the water and nutrients their growing tops need.
In spring, newly planted trees and shrubs are genetically programmed to produce top growth (shoots and leaves), not roots. The trigger to produce roots comes later, during the shorter days and cooler temperatures of fall.
The inevitable spell of hot, dry weather, usually in May, brings on the real test for spring-planted trees and shrubs. The increased demands because of the additional spring growth will outstretch the supplies the limited roots can provide.
The plants become out of balance, top-heavy, with more tops than the limited roots can support. As a result, the plant may begin throwing off foliage and abandoning branches in an attempt to survive.
If you plant now through December, with average weather, the plant has a much better chance. The key is that the roots don’t go dormant. They continue to grow and develop throughout fall and winter.
And because the top is dormant for the winter, there is little demand on the roots.
Fall-planted ornamentals normally have a supply of carbohydrates and other food substances stored in their roots from the spring and summer growing seasons. So, with little demand from the tops, roots can grow and become well established before the next spring.
Actually, the shorter days and cooler temperatures of fall are genetic triggers for root growth, not top growth. As a result, fall-planted trees and shrubs put most of their energy into producing roots, which is an advantage for the plants come spring.
When you plant in the fall, do almost everything exactly as you would do in spring. The difference is that you don’t need to fertilize when you plant in the fall. Wait until after the plants are well established the following spring.
You don’t want to encourage foliage growth but root growth during fall and winter. All other cultural practices would be the same as if you were planting in spring.
After the plant is properly planted, be careful to water as much as it needs. Continue to water as needed through fall and winter.
Plants can be much more forgiving if you’re a day late watering them in the fall. Fall-planted trees and shrubs survive better as compared to those that are planted in spring.
Larry Williams is the Extension horticulture agent with the Okaloosa County Cooperative Extension Service, University of Florida. Contact Larry at 689-5850 or email lwilliams@myokaloosa.com.
