P&PDL Picture of the Week for
October 11, 2004

When Burning Bush Won't Burn!

Rosie Lerner, Extension Consumer Horticulturist, Department of Horticulture & Landscape Architecture, Purdue University

I've received many calls over the years from folks that want to know why their burning bush fails to display the expected brilliant red fall color. There are many factors involved in determing fall color display, not the least of which is genetics of the plant. There is great variation among the commonly sold cultivars, and even more variable among seedling offspring. So the first question to ask is whether this particular plant ever had outstanding fall color? If not, likely it is lacking the genes responsible for great fall color.

If a plant has had great color in previous years, then the cause for poor coloration this year is likely to be related to the environment. Even among the same cultivars, fall color is often not uniform from plant to plant, or even from leaf to leaf on the same plant. Plants or parts of plants may vary in exposure to light, temperature, moisture, nutrients, and stress.

The photo on the left shows little fall color at a time when other burning bush in the area are about at their peak. Despite being the south facing side of the shrub, the overhanging tree branches provide heavy shade.

The photo on the right, is of the northwest facing side of the same shrub, which in this case is not shaded and so has a little better coloration due to higher light levels. However, even this side does not show as brilliant a display as the neighbor's plants. So in this case it could be a combination of genetics and environment.

For a more thorough explanation of fall color, visit the following links.

http://www.hort.purdue.edu/ext/earlyfall04.html

http://www.hort.purdue.edu/ext/fallcolor.html

http://www.ces.purdue.edu/extmedia/FNR/FNR-FAQ-5.html

 

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Purdue Plant & Pest Diagnostic Lab Purdue Cooperative Extension Service