As summer changes to fall, plants in our landscapes change too. Shorter day length and cooler weather bring on changes in our shrubs, trees and lawns.
Azaleas may lose a few leaves now. These are the older leaves on branches near the center of the plant. There is no need for alarm by the loss of a few older azalea leaves from now until spring.
However, if younger leaves, those nearest the tip of the shoot, turn yellow or brown there is cause for concern. Poor drainage, lack of water or alkaline soils may cause this.
Other plants such as gardenias, hollies, camellias and cherry laurel may have yellowing leaves now. But as with azaleas, these are the older leaves on the stem near the center of the plant. Mature leaves will drop from the plant from now until spring. This is the normal aging of older leaves. Be careful to not confuse this normal process with spider mites, scale, lace bugs, nutrient deficiencies, poor growing conditions, salt injury, etc. Just keep in mind that this normal change in leaf color and leaf drop occurs on older leaves during cooler weather – it’s a seasonal change.
Leaves of sycamore trees have changed from green to brown by now. Although sycamore is a deciduous tree, this phenomenon is not caused by a change in day length or temperature and is not considered a true seasonal change. It is the result of insects feeding on the leaves. By the time the damage is visible, there is little that can be done to correct the problem, which is caused by the sycamore lace bug. This problem will take care of itself since sycamore trees will soon be dropping their leaves.
Our lawns also experience some seasonal changes. Growth rate of lawn grasses decreases during fall. This slowdown means less mowing is required and it means that lawns will be less attractive than they were during spring and summer. Weak, thinning and damaged areas of the lawn will show little to no improvement during this time because of this slowdown in growth.
Bermudagrass, zoysiagrass and centipedegrass will turn brown with the arrival of the first frost. Expect some St. Augustinegrass blades to turn reddish purple as a result of cool temperatures and light frost. With freezing temperatures, St. Augustinegrass will turn brown in unprotected areas.
Larry Williams is an agent at the University of Florida's Institute of Food and Agricultural Sciences Extension office in Crestview.
This article originally appeared on Crestview News Bulletin: Autumn creates changes in our landscapes