Timing of late summer preemergent spray for Poa annua

[Pway]

Looking at my notes, I’ve consistently done my Dithiopyr late summer spray the first week of September. I think this has worked fairly well but I still do get some annual blue grass in the spring. I have two areas (front and back near the house) that get a lot of shade. A couple years ago I sprayed Dithiopyr in the back and dropped two applications of starter fert with Mesotrione in the front where I wanted to reseed. The dimension areas defiantly were more effective than the Mesotrione area. I’m thinking of reseeding a Small area in the front and follow the same approach mentioned above. I’m curious to hear other’s thoughts and experiences of two applications,cations of Mesotrione vs Dithiopyr. Thanks

[MorpheusPA]

I actually go with one app of Prodiamine (not what you're necessarily interested in, but hear on)...however, I drop in late August before temperatures fully drop into annua sprouting season. My application is already down and watered in as of today (we just got our promised thunderstorm as temperatures dropped from 94 to 78, which is supposed to happen repeatedly over the next two weeks).

Annua invasions have dropped to two or three, with extremely heavy weed pressure from four surrounding infested properties.

Proper time of application seems pretty important. Too late is, simply, too late. And that one app is coverage for spring as well at the 1.5 tbsp rate.

[Pway]

I actually go with one app of Prodiamine (not what you're necessarily interested in, but hear on)...however, I drop in late August before temperatures fully drop into annua sprouting season. My application is already down and watered in as of today (we just got our promised thunderstorm as temperatures dropped from 94 to 78, which is supposed to happen repeatedly over the next two weeks).

Annua invasions have dropped to two or three, with extremely heavy weed pressure from four surrounding infested properties.

Proper time of application seems pretty important. Too late is, simply, too late. And that one app is coverage for spring as well at the 1.5 tbsp rate.

Thank you, Morpheus. I’ll try to get it down in the next couple of days rather than My usual date (has been September 4 or 5).

[gwlbe]

I just sprayed the last of my Dimension. I would like to switch to granular but for 2 apps a year on 35k, I find it very expensive. Where are ya'll sourcing granular preem?