Pre-emergent lawn treatment refers to the process of spraying the lawn for weeds before they appear. The purpose of using a pre-emergent herbicide is to stop or greatly limit the growth of stubborn, spring and summertime weeds, such as Annual Bluegrass, Common Chickweed, Purple Deadnettle and Henbit, to name a few. These are all weeds that germinate during the winter and begin to sprout and spread at the first signs of warm weather for spring.
How do pre-emergents work?
Applying a pre-emergent treatment to the lawn will create a barrier between the healthy grass above the surface and developing seeds from weeds below the surface. This invisible barrier lies just below the surface of the grass and prevents weeds from breaking through to the surface, in effect killing the weed before it has a chance to re-seed and produce.
When should pre-emergents be applied?
In Alabama, the best time to apply pre-emergents is during the late fall and early winter, when common weeds begin to germinate and take root. If the treatments are applied too late in the season, there’s a chance some weeds will pop through the surface, but if they’re applied too early, when the soil is still warm, it may not be as effective. Treatments should take place before the ground freezes, but after the temperatures are in the 40 to 55 degree range.
How often should pre-emergents be applied?
Just like painting a wall, sometimes more than one coat is necessary to gain full coverage. It’s common to apply at least two, sometimes three, treatments to gain full coverage.
Will a pre-emergent prevent all weeds?
Unfortunately pre-emergent treatments cannot eliminate all types of weeds from entering or growing in the yard. The treatments can greatly reduce hard to remove weeds that appear in the early spring and summer, but some seasonal weeds may still appear, but they will be far fewer and easier to spot treat for removal.
Can pre-emergent treatment only be applied by professionals?
Popular lawn and garden stores do sell pre-emergent products that can be applied to the lawn; however, professional, commercial lawn companies have access to products that can build stronger weed barriers. Additionally, companies that treatment lawns often already have the equipment necessary to effectively and quickly apply pre-emergents.