GRAND RAPIDS, Mich. — The warm weather we’ve been seeing lately isn’t going anywhere quite yet with highs in the 80s continuing this week. Unfortunately for fall lovers, the summer-like feel that sticks around through the weekend is delaying the arrival of peak fall colors.
Deanna Hedlund, the Consumer Horticulture Educator for MSU Extension, predicts a later arrival of peak fall colors, estimating “It seems like we're on this trend with it being a few weeks later than typical, and it is moving to be closer to the end of October than earlier in October, and mid-October that it used to be years past.”
Fall color timing and vibrancy is greatly impacted by the weather and day length. As we approach the Autumn Equinox, our days become shorter and shorter. Longer, cooler nights, send a signal to trees that fall is on the way.
Cooler overnight lows help to break down chlorophyll, the chemical compound that makes up leaves’ green pigment. As chlorophyll breaks down, the underlying yellows and oranges start to show through.
The brighter reds and purples that are often associated with certain trees like maples and oaks are achieved through sunshine. “When you have sunnier days, it triggers the color to brighten of the reds and purples,” commented Hedlund. “Some plants have the ability to do that more than others.”
Vivid, long-lasting fall color requires a balancing act between cool, but not freezing nights and plenty of sunshine, but enough rainfall to avoid getting too dry.
Any rain would also ideally be from gentle showers as opposed to thunderstorms with breezy winds that can blow down a tree’s leaves, transferring the fall colors from above our heads to below our feet.
Fall color isn’t here yet, but when it does arrive, peak color is expected in mid to late October across the Mitten.