Therese from Boise, Id writes
Killzall Weed and Grass Killer - 41% Glyphosate can take up to 2 weeks to completely kill weeds and applying it more often or higher than the labeled rate does not make it work faster or better. In fact, this can actually stress the weeds, making them less likely to absorb the product and die from it. It does only kill the weeds it is directly sprayed onto and does not prevent anything new from growing in the area. The rate used sound to be way to much for such a small area, the highest rate you should use is 2 ½ oz per gallon of water to treat 300 sqft per the product label. At this time we would advise to wait at least 2 weeks from last application and try reapplying ad the labeled rate. Be sure weeds are actively growing and healthy and are not heat or drought stressed for best results.
Answer last updated on: 06/18/2018
