You also get the wisdom of the ages and people who might not have the same experiences. The advice I gave is based on years (and years) of reading and moderating forums for amateurs and professionals. Applying fertilizer on Memorial Day might be too late in your area due to the onset of summer heat, but as a starting point, it is a very easy date to remember. Whether you get disease or not depends also on grass variety, air circulation, dew, humidity, soil type, and other factors. I'm not sure why Georgia would be much different from other places where the taller grasses are the healthier ones. At the same time that the wisdom of the ages sounds like a good idea, you also get the senility of the aged. Tupersan is relatively new to my repertoire of garden products. I became 100% organic before I heard of it and seem to have a block about that product. In general I don't put any faith in preemergent herbicides but people I respect tell me they work. I do recall from my relatively recent reading that Tupersan works as tiemco says. Professional grass growers (livestock producers) fertilize with 1/4 of their annual nitrogen in the spring, and they always apply it after the initial flush of green growth has ended. They apply 3/4 of the annual nitrogen in the fall. They do it this way to minimize their mowing workload and to spread the productive growth along throughout the entire growing season. The wisdom of the ages here at GardenWeb also agrees with tiemco that combination fertilizer/weed killer products are not going to do what you expect them to do and it is better to use different products for the different requirements. Yes Mother Nature has Her own ideas about watering, but for what you do, you do not have to encourage weeds. Far too many people set their sprinkler to operate for 10 minutes every day. That schedule is going to germinate every seed in the garden. You have control over your own watering. Allowing the soil surface to dry out as much as you can will develop deep, drought resistant roots as well as minimize weed seed germination.

Okay, way, Way, WAY, WAAAAAAAYYYYY too much information. Please try to stay on topic. If all your tenant agreement says is "maintain and irrigate," you're screwed. Your definition of maintain and irrigate is apparently different from theirs. It's your opinion against theirs. Your word has nothing to do with it. It's all opinion because you used loose language. If you want to ensure you get 100% crabgrass coverage by July, follow your current plan. If you want to get rid of crabgrass do this... 1. Water deeply and infrequently. You're almost there with the 5-day flood plan. Can you stretch that to 14 days this time of year and gradually work it up to 7 days when the temps get into the 90s? 2. Mulch mow at the mower's highest setting. 3. Fertilize once in the late spring and twice in the fall. 4. WAIT UNTIL FALL to reseed. Crabgrass seed only germinates in the spring and only when it lands on moist soil which remains moist for several days. If you withhold water and allow the soil surface to dry out completely, then you have a shot a not having any crabgrass. But you need a dense turf. Fescue has that problem of becoming less dense over time unless you continually reseed in the fall. So it was not your tenant's fault that you have crabgrass in his lawn.

There is a problem with timing on the Scott's product. If you apply it on time for the Halts to work, then you have wasted the fertilizer. If you apply it on time for the fertilizer, then you could have crabgrass growing before you ever put the product out. It would have been better to apply straight Halts back when the forsythia first started to bloom and then wait until your actual grass has been mowed at the highest setting on your mower for the second time. That way you are sure to apply fertilizer to actively growing roots. But that is all water under the bridge. Do you have any chance of the new seed sprouting? I would say you do have some chance. You might have a better chance if you went out right now and sprinkled new seed on top of the soil and stepped on it with your full weight to press the seed into the surface of the soil. That is how Mother Nature reseeds her prairie grass. Bison, antelope, buffalo, zebra, horses, and other ungulates remove the grass, knock the seed onto the soil, step on it, leave their dung (you can skip this step) and leave the area. The reason you can skip the dunging step is because the importance of that step is the dung beetles that come along immediately and bury the dung in 3/4 inch diameter holes about 6 feet deep. That's not going to happen in your lawn whether you leave dung or not. But you'll notice that the seed is not buried in Mother Nature's method. It falls on the surface and is not mixed in with the top layer(s) of soil. I think the underlying Halts is not a problem for your seed. This is a good experiment. Please let us know how it comes out.

Even without a pre-emergent, summer survival of spring planted grasses is touch and go (the pre-em actually doesn't cost you much, if anything at all). They simply don't have time to develop adequate root mass before summer hits. Consistent watering can get you around that...and of course, can also set off some nasty fungal issues. But those can be dealt with as they arise. Tupersan or Tenacity are fine at seeding time, and can be reapplied. Once. That will get you through the silly season of weed growth and into the earliest part of summer. Post that, the optimal answer is to wait until the grass has been mowed three or four times, then spot-spray weeds that do sprout and use a pre-emergent again at that point. Crabgrass will continue to sprout until soil temperatures drop under 65 or so (it's most energetic warmer), so even a late-applied pre-emergent has some benefits. You're likely to still have breakout issues for some years. Pre-emergents are around 90-99% effective. Crabgrass can drop hundreds of seeds per plant without half trying. So some will still sprout. Fortunately, Weed B Gone with Crabgrass Control is very effective on sprouted crabgrass, and can be spot-sprayed even when the lawn is very young. It may damage or kill some surrounding grass at that point, however. By the third or fourth mow, the grasses will be much more resistant to it and damage will be minimal, if any at all.