When applying broadleaf weed control to newly planted grass seed you must wait until the newly sprouted grass has been mowed three times or wait for at least 30-days, whichever time frame is longer.
If applied too soon after grass germination broadleaf weed control will adversely affect young seedlings, either killing or weakening them. Keep in mind this three-mow rule is for new grass, not for seeding into an established lawn. The rate of growth for established lawns is different than that of seedlings.
For further information on how and when to apply Jonathan Green’s Green Up Weed & Feed and Lawn Weed Control please visit our product pages. Before applying any herbicide, carefully read and follow label directions.