By Claryssa J. Medina, Somervell County Master Gardener Intern
If you’re out and about these days, no doubt you have seen a sign at lawn and garden departments that says “Time for Pre-Emergent’. If you are a diligent turfgrass advocate, you probably already know the time is indeed upon us. What you may not know is that all pre-emergents are not created equal. Choosing the right pre-emergent is important for the continued beauty and health of your lawn.
The purpose of a pre-emergent is to prevent the germination of weed seeds. An application in spring and fall is ideal.
Apply in early September for winter annual weed control. The targeted weeds for this fall application are the ones that will be growing rampantly in the late winter and spring.
While it is somewhat less important in spring, when choosing a pre-emergent for fall you will want to choose a granular herbicide that has no nitrogen and apply with a spreader. Apply in early September for winter annual weed control.
Why no nitrogen? Especially in the fall, the risks of increasing nitrogen are:
1. It extends the mowing season and increases clippings;
2. You will gain shoot growth over root growth;
3. It will deplete stored energy in your turfgrass;
4. Possible fertilizer burn;
5. It encourages annual winter weed growth; and
6. Increased liklihood of disease.
Another note of caution is not to choose a slow release fertilizer near the end of the growing season, when turfgrasses are on the verge of dormancy.
Don’t forget – the goal is uniform coverage and water it to activate it.
With proper management and preparing the ideal turfgrass environment, you’ll be on your way to getting the “yard of the month” award!
May all your gardens be green!
Resource: Texas Master Gardener Handbook