Scotts with Halts will prevent grass seed from germinating. There is a new starter fertilizer that contains an ingredient called Mesotrione, which is safe to use on newly seeded turf, and will prevent weed germination. Keep in mind that fertilizer now will force topgrowth of your existing grass, which can interfere with your efforts to grow new grass, sort of a catch 22.

Thanks. So what would you suggest to do? I'm a rookie with this stuff but I really want to learn and make it look nice.

If you are going to put down a pre-m (crabgrass preventer) you will want to do it soon (when the forsythia bloom). Otherwise it wont prevent the CG. The pre-m with mesotrione (or the one with siduron--both a Scotts products carried by the big box stores) only gives 6 weeks as a preventative, so you will want to get your seed down shortly before or after applying that pre-m.

If you are going to put down a pre-m (crabgrass preventer) you will want to do it soon (when the forsythia bloom). Otherwise it wont prevent the CG. The pre-m with mesotrione (or the one with siduron--both a Scotts products carried by the big box stores) only gives 6 weeks as a preventative, so you will want to get your seed down shortly before or after applying that pre-m.

Are you overseeding the whole lawn, or just trying to fill in some bare spots?

I am planning on putting fertilizer on the whole lawn. There are only a few bare spots which will need new seed.. I think?

Would it work if I fertilized with the crabgrass prevent and then sometime in may plant the seed in the bare spots?

Thanks

Here are the basics of lawn care.

2. Water deeply and infrequently. Deeply means at least an hour in every zone, all at once. Infrequently means monthly during the cool months and no more than weekly during the hottest part of summer. If your grass looks dry before the month/week is up, water longer next time. Deep watering grows deep, drought resistant roots. Infrequent watering allows the top layer of soil to dry completely which kills off many shallow rooted weeds.

3. Mulch mow at the highest setting on your mower. Most grasses are the most dense when mowed tall. Bermuda, centipede, and bent grasses are the most dense when mowed at the lowest setting on your mower. Dense grass shades out weeds and uses less water when tall. Dense grass feeds the deep roots you're developing in 1 above.

4. Fertilize regularly. I fertilize 4 times per year using organic fertilizer. Which fertilizer you use is much less important than numbers 1 and 2 above.
   

For your current issue (large bare spot when you pull up a plant) you need to know what kind of grass you have. Some grasses will spread to fill in without adding more seed. And if you add the wrong seed, you can ruin a lawn. Can you find out what type of grass you have?

Dchall- thanks for the reply. It's very helpful. I will try to find out what kind of grass I have. Thanks!

The best solution would be to cover the bare spots to prevent the crabgrass preventer from settling in those areas. Halts isn't paricularly long lasting, so you might be ok even if you do get some in those spots. One other thing, it's a bit early to be fertilizing, so if you can get just straight preemergent, with no nitrogen, that would be a better choice.

Ok. So my plan of action should be to not fertilize, but to put new seed down and also use a pre emergent now. Then maybe fertilize Ina couple of months. Then oversexed this fall. Is this correct?

Thanks

And also do what dchall recommended