When to Spray Weed Killer

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Weeds harm the growth of other plants.

Weeds are nuisance in the garden. They compete with desirable plants and vegetation for moisture, nutrients and sunlight. Applying commercial weed killer controls weeds. Before applying, consider soil type, climate and plant types. Herbicides can contain harmful chemicals, so ensure your pets and children avoid the garden around when you apply weed killer.



Apply weed killer in late spring for optimum results. Due to the cyclical nature of growth, weeds are young and fragile at this time of year, making it harder for them to endure the effects of chemical weed killers.


Avoid using weed killer on hot days. Herbicides applied in hot weather can damage to your lawn. Wet days are also bad times to apply weed killer to your lawn. Commercial herbicides need 24 hours in a dry, clement climate to work. Spraying on windy days can also be ineffectual, as substantial amounts of herbicide will be lost the airflow.


Pre-emergent Weed Killers

Tackle weed problems before they appear. Pre-emergent weed killers restrict seed germination and are especially effective at controlling annual weeds, such as crabgrass

Spot Treatments

If your garden is healthy, use spot treatment for any weed problems rather than a blanket herbicide for the whole lawn. Herbicides can stress desirable plants, as well as unwanted weeds.


Lawn Maintenance

Mowing your lawn a few days leading up to applying weed killer can reduce its efficiency. Weed killers work when absorbed by leaves. The more leaves, the more effective the weed killer. Avoid mowing your lawn for a few days after application as well, as herbicides need time to work into the leaves.