Can I add anything to the soil to make my tree display prettier fall color?
A. If soil is too alkaline for pin oak, its dominant colors are brown and yellow. But if you add acid to the soil, and weather conditions are right, pin oak can turn bright red in fall. Other than this one exception, we can’t improve the fall color of our street trees. Q. Are very colorful trees telling us they are healthy? A. A colorful autumn is just that—colorful, according to Hedborn. Color does not indicate a plant is healthier or weaker, just that the environmental conditions are good or are poor for color production. “Plants with problems can have leaves that change color, but the color can be brown, yellow, or admittedly in some cases orange or red. But it is not predictable,” said Hedborn. At the Arboretum Learn the latest about eco-friendly garden design at Gardeners’ “Night Out” 6:30-9:00 p.m. November 6. $60 (discount for members), includes buffet dinner. Registration open now, call (630) 719-2468. Laurie Casey is a staff writer for The Morton Arboretum.
