According to my horticulturist husband, the answer is…..”When the Forsythias are in bloom!”
Phenology is the study of recurring events in the life cycle of different species and learning how such events are interrelated throughout that species and other species.
Forsythias reach full bloom when soil temps get up to 55 degrees Fahrenheit. Coincidentally, Crab Grass seeds also germinate when the soil temps are at 55degrees Fahrenheit!
Therefore, those yellow flowers blooming on forsythia bushes as a phenological symbol, or nature signal, telling you, “Hey! It’s time to throw down some Crab Grass preventer!”
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