Killing weeds is a summer-long process. Now that the dog days have arrived, the heartiest of the weeds have survived…and a few new faces have started playing around the neighborhood, as well. It’s a great time to spot treat the weeds in your yard. You might think that the best time to hit ‘em with a sprayer is the hottest, driest day. Wait until they’re really thirsty – then soak those bad boys with poison! That theory makes sense.