Originally Posted by Red Leader
Well, to be honest, I don't remember what we had decided that it was. Even with the pictures, you weren't completely sure, IIRC. I know henbit was in the discussion, but there were others we discussed as well. We have a pretty decent sized yard (~1 acre). I might buy the broadleaf herbicide for the normal weeds that pop up in our lawn. I'll probably wait until the spring to kill off the stuff that is blanketing my backyard. I thought it would be smarter to aerate before overseeding so that the new seeds had room to settle in and more oxygen / nutrients could get to it? You're saying just go ahead and overseed now and then aerate after?
Okay, this is where it gets a little complicated.
possible thing to do is this:
aerate, topdress, fertilize and then overseed
However, most homeowners don't want to topdress, which is a pretty labor intensive process. But topdressing is the thing that puts your seed into contact with some kind of medium that will be conducive to germination. Additionally topdressing with organic matter is great because that stuff falls down into the holes created by the aerator...which is like injecting your lawn with a soil conditioner.
But, like I said, most homeowners don't want to take this on, and you will need a way to create a good environment for the grass seed to germinate. So, I tell them to rough up the brownest patches, then overseed, then mow with a mulching mower. It's a cheat, basically. The mown grass will provide a mulch cover in which the seed can germinate. If you keep it watered then that grass will take root. For the brown spots, I recommend roughing up and leaving the dead stuff. Overseed then rake lightly, just like planting new seed. But keep it watered- newly germinated grass needs water.
Still, I think it's best to do this before the temperature drops below the 80s in the day time. You could aerate before you do this, but if you are not topdressing, I'd aerate after the new grass has been mowed a couple times.