by Dan Harrell
Crabgrass. Even the name sounds like something we don’t want in our home lawns. Besides being an eyesore, weeds like crabgrass compete with our lawn grasses for water, sunlight, and essential nutrients.
I’ve got good news! Because crabgrass is an annual weed and must come back from seed each year, we can control it by applying a pre-emergent herbicide to the soil that will kill young, germinating seedlings.
Here’s the skinny. Crabgrass germinates when soil temperatures reach 60 degrees F for three consecutive nights. The key word here is PRE-emergent. We must apply BEFORE this warming period for it to be effective. Of course we can always use a soil thermometer. Or, we can listen for the whisper of nature.
Forsythia bloom when the soil temperature is around 55 degrees and this signals a short window of time before the soil reaches temperatures needed for crabgrass germination. Forsythia blooming is a signal for me to get off my duff and get outside. In this case Nature does not shout, she only whispers.