We all enjoy the colors of autumn – yellow, orange, purple and red. We love fall color so much that many people travel far to the north and northeast each year to witness the forests ablaze with turning leaves. Some of us even design our landscapes around fall color by choosing special trees and shrubs known for their brilliant color. But what happens when these same plants don’t turn that designated color, such as with red foliage? Read on to learn more.
Red Fall Foliage
Trees with red leaves have a powerful impact on the autumn landscape. It is striking how they glow in the autumn sunlight. But sometimes our plans go awry. That “Red Sunset” maple or the “Palo Alto” liquidambar tree turns brown and drops its leaves without a whisper of rosy glow. Why foliage doesn’t turn red is a frustration for gardeners. What went wrong? When you buy a tree at a nursery described as having red fall foliage, you want red fall foliage.
In the fall, it is the drop in temperature, the loss of daylight hours and other chemical processes that cause chlorophyll production to cease in trees. Then green leaf color fades and other colors come forth. In the case of red leaves, anthocyanin pigments are formed.
Why Foliage Doesn’t Turn in Shrubs or Trees with Red Leaves?
Sometimes, people accidentally buy the wrong cultivar and the tree turns yellow or brown instead. This may be due to oversight or even mislabeling at the nursery.
Red color in leaves is best when autumn temperatures are below 45 F. (7 C.) but above freezing. If fall temperatures are too warm, then red leaf color is inhibited. Additionally, a sudden cold snap below freezing will reduce red fall foliage.
Trees with red leaves may fail to turn red if the soil is too rich and overwatered. These trees will often stay greener longer than others and may miss their colorful window of opportunity.
Solar exposure is important too, as in the case of burning bush, for instance. If it is not planted in a sunny location, the red fall foliage won’t form.
Trees and Shrubs with Red Fall Foliage
There are many shrubs and trees with lovely red fall foliage such as:
Keeping red trees red partially depends on the weather. You’ll get your best performance with cool but not freezing autumn temperatures.
If you are wondering how to get red foliage, consider the following:
- Don’t over fertilize or over water your trees in the fall.
- Make sure your tree is planted in the right conditions. A sun lover planted in the shade, for example, will perform poorly.
- Make sure your tree has the proper soil pH – a burning bush might not turn red if the soil is too acidic or too alkaline. In this case, amend the soil to correct its pH.