FALL INTO COLOR
Trees put on final show of the year as they prepare for winter
I’m always surprised how late our trees show fall color. The oaks, maples, sweet gums, crapes, cypresses and sumacs seem to have peaked overnight.
Why do leaves change colors? They lose chlorophyll, the predominant pigment that makes them green and nourishes the tree.
When days become shorter and nights longer as a tree prepares for winter, chlorophyll production slows or stops. As the green disappears, yellow carotenes and orange xanthophylls become more visible.
Weeks of cool night temperatures above freezing and warm, dry, sunny days have encouraged the production of red and purple anthocyanins. Leaves continue to make sugar on such days, and it’s trapped in the leaves, triggering the red color in maples, sweet gums and sumacs. Tannins are the brown pigments typical in oaks.
If you’re looking for trees to add fall color to your landscape, maples, Texas red oak, sweet gum, tallow and Bradford pear reliably provide fall color.
The native Drummond maple is a good one for Houston. Its leaves may be mostly golden yellow some years, but it offers broader splashes of red other years.
The Shantung maple also tolerates Texas heat and our alkaline soils. And for those who would love a maple but don’t have room for a large shade tree, it is ideal for smaller urban gardens. It has been designated a Texas Superstar, recognition reserved for superior landscape plants for most of our state. Good drainage is key.
Looking for a drought-tolerant sugar maple? Acer skutchii, a Mexico mountain sugar maple, is making waves in Central Texas trials for durability, growth rate and alkaline tolerance.
Q: Does frost cloth protect plants from freezing? Sally Sims, Houston
A: While the fabric is lightweight, it does help protect tender vegeta-