We use Roundup. It can take about a week or even longer in this cool weather to show the beginning of yellow grass. I'd figure your's will be aobout the same. It works way better in HOT HOT weather but it will work in the cooler weahter, it just takes longer. I will give one bit of advice, be sure to follow directions. It is not something to mix up stronger, stronger is not better, just harder on everythng else. This is one of those things that stuck with me from many years ago while taking a Master Gardener class. They had a sales rep from the chemical company come talk to us about using chems and that one thing was stressed, always mix according to directions.
Good luck with your spray, Mona
