I've too read that the extra nitrogen should help speed green up in the spring. At least that's the theory. Honestly I have not paid enough attention in the past to notice. But last year I didn't fertilize much all year and this year my yard didn't completely green up and fill in until July. I think one of the problems was my 4 inches of dead grass on top in the spring prevented the soil from warming up quickly in March and April. This year, on Labor day I applied Lady Bug 8-2-4 (after CGM, CM, Greensand and SBM in previous months) and next month I may apply 50# of SBM to see how much it helps next spring. The yard has been organic 4 years now, so I'm trying to cut back on the fertilizing again.

Applying a Nitrogen source in the fall will allow the grass plants to store that N and be ready in the spring to grow really well as soon as the soil is warm enough for the grass to grow.

Thanks to you both for your replies.