Is it too late to put down the crabgrass treatment? It is early April. This means The Masters Golf Tournament, beautiful flowers blooming, and getting your crabgrass preventer lawn treatment down. The best way to control crabgrass is by getting down the barrier to protect your lawn with a preventative treatment in the Early Spring. Is it too late to put down the crabgrass treatment? No. Everything is dictated by soil temperature. The soil temperatures in our area are still quite low. We do not start worrying about how effective the crabgrass pre-emergent treatment will be until the soil temperatures reach 55-60 degrees consistently. There is plenty of time to get the crabgrass lawn treatment down. We will be doing our first lawn treatments through April and the barrier will be completely effective. Do not wait though because this lawn treatment is time sensitive. Applying your preventative crabgrass control too late in the Spring can lead to ugly clumps of this crabgrass (a summer annual grass) popping up in your yard in July.