“April showers bring May flowers,” but that moisture also brings a lot of weeds. Here’s some information on combating weeds, before they grow and after they’ve arrived.
Warmer temperatures are on the horizon, and as soil temperature increase, so will weed germination. As a landscape professional, your number one defense against weed germination comes in the form of pre-emergent herbicides.
In lawns, defending against weeds is made easier when the lawn is healthy and dense. This is achieved when you properly include water, fertility, and disease, insect, and weed control into your program.
Using Herbicides to Control Weeds
While there are many weeds and they vary by region, some of the most common weeds you may encounter this spring and summer are crabgrass, dandelions, clover and goosegrass.
You can control these weeds with pre-emergent herbicides, which prevent the weeds from establishing, or post-emergent herbicides, which are used after the weeds have germinated. They include non-selective herbicides that kill everything, and selective herbicides that target specific broadleaf or grassy weeds.
The chemical you use will depend on the part of the country you are in and what specifically you are targeting.
- For broadleaf weed control, use Trimec 992 or Speedzone (post-emergent herbicides).
- For summer annuals in turfgrass, use a pre-emergent herbicide like Dimension, Barricade or Pendulum.
- For ornamental beds, use Snapshot or Freehand (pre-emergent herbicides).
Pre-Emergent Herbicide Options
|Chemical Name||Trade Names|
|Bensulide||Betasan, Bensumec, PreSan|
|Dithiopyr||Dimension, Dithiopyr 2L|
|Ethofumesate||Prograss 1.5 EC|
|Oryzalin||Surflan 4 AS, Oryzalin 4L|
|Oxadiazon*||Ronstar, Oxadiazon 2G|
|Prodiamine||Barricade, Prodiamine 4L|
|Simazine||Princep 4L, Simazine 4L, Simtrol 4L|
Tips for a Successful Pre-Emergent Application
- Pre-emergent applications to control summer annual weeds must take place in the spring prior to soil temperatures reaching a 55-degree average at a 4-inch soil depth.
- Always make sure you read the label to ensure the product controls the weed species you’re targeting, and use proper application attire!
- Check your local extension service or a Ewing turf specialist for proper timing of the application.
The weeds you encounter, and the herbicide you’ll need to fight them, will vary across the country. Visit your nearest Ewing location for help in selecting the best herbicide choice.