Wednesday, September 25, 2013

Stop Winter Weeds Now with Pre-Emergence Preventers!

Crabgrass in bermuda,
WikiMedia Commons
Fall application of crabgrass preventer now will prevent a lot of lawn weeds in Bermuda, Zoysia, Centipede and St. Augustine lawns during the winter. Now is the time for Crabapple LandscapExperts to apply pre-emergence herbicides to the properties you manage in order to P-R-E-V-E-N-T the cold-season weeds from sprouting. In winter, Bermuda and Zoysia turf goes dormant and turns a light tan color. This makes the rapidly-growing, bright green chickweed, henbit, or annual bluegrass stick out like a sore thumb. Other times of the year, broadleaf and grassy weeds “blend in” with the green of actively growing lawngrass.

Pre-emergence herbicides eliminate mainly annual weeds by preventing their seeds from sprouting. They can be applied in granular or liquid forms, and do not typically damage shrubs, trees and perennials. Well-established turf is not noticeably affected by the pre-emergents, and it is pretty safe.  Once the application is complete, Crabapple will water-in (or if rain is predicted, so much the better) the pre-emergent herbicide to enable it to create a barrier to seed germinating on the soil surface.  

Purdue Cooperative Extension
The timing varies from year to year, but typically metro-Atlanta’s average best time to apply is the last week of September through the first part of October, coinciding with nighttime temperatures around 55 or 60 degrees F. It’s not a problem to apply the pre-emergence herbicide too early, except that it may wear off sooner. But if Crabapple puts it down too late, some of the weed seeds will have already sprouted, and be on their way to becoming an unsightly green interruption in the turf you manage.
One caveat is that if you have contracted with Crabapple to overseed with annual ryegrass over the top of your turf in order to maintain the green color all winter, then pre-emergence herbicides should not be used, because the annual ryegrass seed also will be prevented from sprouting. Another caution, Crabapple does not recommend Weed-And-Feed after about mid-September, in order to reduce both the incidence of disease and the cost to our customers. 

Pre-emergence herbicides are a great way to control winter weeds, but not a panacea. Crabapple will still need to spot-treat resistant perennial weeds such as dandelions and wild onions with a broadleaf weed killer during the winter. For more information, call your Crabapple Rep to discuss pre-emergent herbicide to keep the lawns in your community looking perfect at 770-740-9739.

Digging Deeper:
UGA has a Suggested Weed-Control Calendar. 

1 comment:

  1. Granular pre-emergence herbicides can help manage winter weeds in the lawn when applied prior to weed germination.