Pre-emergent season is upon us. Soil temperature, moisture and sunlight determines when a seed will germinate. The pre-emergent must be applied and active before that magic moment occurs. Remember that your goal is always to apply the pre-emergent BEFORE you can see the weeds — before their seeds sprout.
The all-natural pre-emergent is Corn Gluten Meal. It is available in both granulated and powder form and it is applied at a rate of 20#’s per 1,000sf. The synthetics are Dimension for the grassy weeds and Gallery for the broadleaf weeds. The key to all of these is the application rate. Follow the label directions and know the square footage of your lawn.
I am asked (a lot) when to put out pre-emergent. Conventional gardening wisdom says spread pre-emergent herbicides when the daffodils pop or the forsythia wilts. In a perfect world I will get it out and watered in the second weekend of February. My world isn’t perfect and our current water restriction have put a kink in my plans. So I shoot for mid-February to the first of March. A little work now, will yield beautiful results later!