Answer: It sounds as though a major renovation is in order! Weed and Feed should take care of the weeds in your lawn. If it didn't, the weeds are either firmly established with big, huge roots, or you didn't apply in the correct amounts. It's also possible that you have such a thick layer of thatch that the herbicide couldn't penetrate into the soil to kill the weed roots. In any case, I'd suggest redoing the lawn this fall. Try digging out the largest, most tenacious weeds. Then start the renovation process by power raking (you can rent aerators or power rakers at most garden centers). These heavy duty machines will help pull out the thatch and will roughen up the soil to receive new seeds. Once you've raked the dead stuff out, you can broadcast grass seeds over the entire lawn. When the new grass is up and growing strong, you can use weed and feed to get rid of the remaining weeds. Next spring put your lawn on a regular watering and feeding schedule (April, June, September and November). The result will be a thick, lush lawn that will crowd out most weeds.
Good luck with your project!
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