In weed prevention and control, there are two types of herbicides used: Pre-emergent herbicides and Post-emergent herbicides. Correctly using these weed killers during the year determines just how effective our weed control efforts will be.
Pre-emergent herbicides is usually used before plants begin to grow, thus the name, “Pre-emergent”. They’re best used when the soil is beginning to get warm.
This herbicide is available in both liquid and granular forms. Regardless of which one is used, the soil absorbs both. When granules are used, using sprinklers easily activate the granules.
Pre-emergent herbicides are more effective on weeds that sprout from new seeds. Weeds like crabgrass.
Post-emergent herbicides are used once the plants have started to grow, as it’s already too late to apply any pre-emergent herbicides.
These herbicides work at the root system of the plants. The liquid form is applied diretly to the weeds while the granular from can be applied with a spreader and activated with sprinklers.
Unlike the pre-emergent weed killers, these herbicides need to be applied periodically during the growing season.