GLT's Grow: The Science Of Fall Color | WGLT

GLT's Grow: The Science Of Fall Color

Oct 20, 2017

As the days get cooler and shorter, nature puts on a gorgeous display of color as the leaves change—red, yellow, orange and, yes, even brown.

  • In the fall, the trees show you their REAL color. Leaves are green due to chlorophyll and photosynthesis. 
  • But when the production of chlorophyll slows and then stops as the season begins to change, then the chlorophyll disappears completely and VOILA! We see the leaves in their true glory.
  • A number of things factor into the change to fall colors. Decreasing hours of sunlight and decreasing of photosynthesis helps lead to the abscission layer blocking transport of materials from branch to the leaf. That loss of connection shuts off the chlorophyll production.
  • As time goes on, that abscission layer gets dryer and dryer and the leaf breaks off from the tree. Now it's time to rake. Or maybe not. We'll cover that next week.
  • A growing season with a good amount of rain that's followed by dry, sunny autumn with warm days and cool nights provides the best conditions for development of the brightest fall colors.
  • The display can continue for weeks, if we don't have too much wind and rain, which knock the leaves off prematurely. 
  • Some trees to consider for good fall color include that old standby, the Sugar Maple, Black Gum, Aspen, Sweetgum, Sassafras and Honey Locust.

GLT's Grow is your source for sage gardening advice and down-to-earth tips. Host Patrick Murphy and co-host Laura Kennedy are ready to take on all your gardening questions, so submit yours today.

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