Check the listing for details. Weed Grass Killer 1 Gallon Concentrate Visible Results in 3 Hours, 2 Pack. Condition: New. Listed at 20.97 USD. Weed Grass Killer 1 Gallon Concentrate Visible Results in 3 Hours, 2 Pack Spectracide Weed & Grass Killer is a non-selective weed and grass killer that kills weeds and grasses. It’s formulated for spot treatment of weeds and grasses on patios, walkways and driveways; around flowers, shrubs and trees; and along fences and foundations. This formula is rainproof in 15 minutes — rainfall or watering after 15 minutes won’t wash away effectiveness. Spectracide Weed & Grass Killer kills down to the root and delivers visible results as fast as 3 hours. Plant new flowers, trees and shrubs in the treated area after just 1 day. For best results, apply this ready-to-use spray during warm, sunny weather when the temperature is over 60 degrees. Completely cover the leaves of the target vegetation. Protect desirable plants with a piece of plastic or cardboard — if desirable plants are accidentally sprayed, wash with water immediately. Do not mow, cut or otherwise disturb treated vegetation for at least 7 days following application. Do not use on or around edible feed or food crops.•Spectracide Weed & Grass Killer, Ready-to-Use, 1 Gallon •KILLS WEEDS AND GRASSES: Use on driveways and walkways, and around fences, trees, flower beds, shrubs and other listed areas.•KILLS THE ROOT: Visible results as fast as 3 hours — replant new flowers, trees and shrubs the same weekend. •RAINFAST: Rainfall or watering 15 minutes after application will not wash away effectiveness.•READY TO USE: Spray to completely cover the leaves of the target vegetation.