Weed killer for St. Augustine & Centipede lawns with atrazine. Controls tough weeds as listed, and it won't harm your lawn when used as directed. This hose-end concentrate formula kills established weeds, including dollarweed, sandspur, and Florida betony, and prevents weeds from emerging in your lawn. Simply connect your hose to the QuickFlip hose-end sprayer and flip the switch to activate. Spray your lawn until wet to control weeds. The spray controls both emerged weeds and weeds from seeds. Apply to all varieties of St. Augustinegrass and centipedegrass when temperatures are below 90 degrees. Do not apply when temperatures are above 90 degrees because injury to your lawn can occur.