I struggled with this question too. I think late Sept/early october may be a little cold for timely breakdown of Milorganite. I am going to try a synthetic fertilizer mid fall and then again late fall.

Late Sep should be just fine for Milorganite in our area. I see nothing in our regional predictions that says an early freeze. Last year I put down 46-0-0 on Thanksgiving weekend and had great results. The nitrogen should go down when top growth has ended for the season. Normally, we have had one or two frosts by then which tells the grass to go dormant for the season.

If it was just sodded this year, go heavy with synthetics for the rest of the year. It is used to that (since that is how it was grown), and needs it. And no matter what your soil test tells you, make sure you give it a good amount of phosphorus (the "P" in NPK) to encourage root growth. Sometimes one can have a good amount of P in the soil, but in a form that is not readily available to new roots/plants, like yours. A starter fert might be ideal for your next feeding. But whatever you use, DO NOT MISS the late fall (after the grass has stopped growing) feeding. I did last year and came to sorely regret that.

Next year, after your initial feeding after the grass has started to green up, go ahead and try the organics. But right now, when roots are actively growing, or looking to grow, for the first time since you installed the stuff, it needs heavy feeding, with synthetics.

Just my $.02 of course.

Good luck!
Paul

Anyone else? I need to make the call this weekend because of upcoming travel.

I can hit with Milorganite this weekend, and then go synthetic in mid/late Oct. and again in Nov.

Or I can start in with synthetic soon, perhaps next weekend, with one or two more in the fall.

Temps in DC are projected to be mid-70s in day and high 50s at night over next 10 days, which is a bit cooler than typical for this time of year, but not by much.

You could go either way. All synthetic or a mixture of milargonite and synthetic this weekend and all synthetic in October.

As for me, I would prefer to mix in some organic to help feed the soil microbes and get some organic matter in the soil. Meanwhile the synthetics would directly help the grass and roots now which is key to a nice spring green up.

Previously here in NC I reseeded in early Sept with a starter fert, apply another full app chem fert in mid Oct and again in mid to late Nov. Now NCSU is suggesting a full app in mid Oct, half application in Nov, and a full app in mid Feb. Check table 6c in the link.

Here is a link that might be useful: link

Jim, I am guessing that they have changed their recommendation not for the sake of the grass, but rather for politically-motivated and not-well-thought-out environmental "concerns" that affect maybe 5% of all real estate - those properties bordering or very close to stagnant or extremely slow running water.

Suffolk County, NY (on LI) has just banned the late fall feeding, effective next year, mostly for political reasons as far as I can tell, since that island (where I grew up) is nothing but a mountain of sand plus a few scattered glacial erratics, here and there. I suspect something similar is going on where you are.

A full app in mid-Feb sounds a little extreme, to the point where it may even hurt the grass by encouraging topgrowth too soon, leading to failure in summer. Maybe that recommendation is intended to make up for the lost late fall feedings which are apparently politically unpopular now, but that doesn't make the recommendation any more right as far as your grass is concerned. And nevermind that a late winter-early spring feeding is much more likely to leach out without any effect on the grass than a late fall feeding, though I guess we are not supposed to notice that. ;-)

Anyway, hard to say what to do other than to obey any laws, but seriously read between the lines of all of these "recommendations." If still allowed in your area, I would favor a late fall fertilizing over one in early spring by a big, big margin.

Paul

Yep, they were recommending a starter fert in Sept when seeding, then a full compliment fert in Oct and again in late Nov when the growing season has ended. Your reasons for the change-up are as good as any, I guess. Beats me, but we do have many streams and rivers that are in bad shape for the last several years, even to the extent of many fishkills, but a lot of that has been blamed on many of the hogfarm runoffs and holding ponds in the state...being that NC is one of the leading sellers of pork products.