You will be fine just water in at recommended .5" of water. Next time you have someone apply a product to your yard make sure they calibrate the spreader with the product they are using. Also make sure you 13000 sq. ft. of lawn and not 15000.

Roger505, The great thing about Dimension is it will kill crabgrass post emergently up to five leaves, before it tillers. So, this gives you a larger margin of error when applying Dimension. That being said, if you keeps you up at night then go ahead and apply the Dimension it's not going to hurt anything. Preemergent timing, along with everything else involved in the care of your lawn, is going to have a learning curve. Use your meat thermometer and measure your soil temp at the same time everyday for three days and record the average temp. Apply your preemergent, then if you get some early crabgrass say in middle to end of April, then you know you applied your preemergent to late and next year you can apply at a lower soil temp. Also, it would not hurt to invest in the herbicide Acclaim herbicide, just in case you make any mistakes with your preemergent application. Acclaim is expensive, but it will last you years. As far as your fertilizer app. goes, I would hold on to the fertilizer that you just purchased and use it in the fall, if your soil test indicates that all the nutrients in the bag are not in the excessive range. Also, just for your edification that bag of "slow release fertilizer" is only around 30% slow release. So if you apply 1 pound of nitrogen per thousand square feet then .7 of a pound of nitrogen will be quickly available to the plant. This is ok in the fall, but in the spring you will be mowing your yard twice a week to keep up. A better option would be .25 to .5 pounds per thousand of ammonium sulfate or urea now. Then when you get your soil test back follow their recommendations plus add .75 to 1 pound of N per thousand that is at least 70% slow release. Henbit usually takes a couple of apps to kill, and herbicides take a little longer to work in the early spring because of the cooler temps.

Ah, OK, I thought perhaps I have having a bit of a psychotic break or something. Your calculation breaks down to well over 3 lbs of nitrogen (back, 4 in the front) per thousand square feet. For any synthetic (numbers like 20-10-10 will be synthetics), that's way, way, way too high. You run a very severe risk of burning the lawn and killing it off, even with the alkaline soil. I feed organically and won't exceed 1.5 lbs of nitrogen at one application--and organics aren't risky in that department. Burning is caused by an excess of salts in the lawn, and synthetics are very high in salt. That forces your lawn to reverse water out of the roots and into the soil (reverse osmosis, in other words), which renders it bone dry and kills it. Even if you got away with it, most of that nitrogen is either going to gas off the lawn, wash away into the rivers, or go into really excessive top growth. You don't want that as all three are a waste. One suggestion is to go organic, which has no salt, will help moderate your pH at the same time, and improves the soil--plus gets the N-P-K monkey off your back a bit. Oh, it also feeds gradually over time instead of one spike and then nothing. There's an entire forum about this (Organic Lawn Care) if you're interested. 'Nuff said. If you'd rather go synthetic, no more than 1 pound of actual nitrogen should be applied at one time (there are exceptions for warm season grasses, but you don't have those in Indianapolis anyway). Note, I wouldn't normally break things this way, but with an overseed coming up, I'm modifying things a bit. Others will have differing opinions and their timing isn't wrong, just different. I'm assuming you can get a fertilizer around 25-5-5 (about that of Turf Builder, Turf Builder plus Iron, and a thousand other off-name brands) for the below. There's nothing wrong with bargain fertilizer, and Vigoro does the same job somewhat cheaper. Store brand is usually one of the large companies and does the same job MUCH cheaper. If you get something different, the equations are: Take square footage in thousands (so your back yard is really 9 as I don't bother with minor decimal points, and the front is 3). Take the values from the bag as a decimal (0.25, 0.05, and 0.05). Take 1/bag value and then multiply by the square footage. That's the number of pounds per thousand square feet to apply to get 1 pound of a given nutrient. Generally I use nitrogen because that's the highest number on the bag. So 1/0.25 * 3 = 12 lbs of 25-5-5 in the front, or 4 lbs per thousand square feet of your fertilizer. That's exactly 1 lb per thousand of nitrogen. You can then calculate the other two values by: 4*0.05 = 0.20. So you're adding 0.20 lbs of phosphorous and 0.20 of potassium. Out back, 1/0.25 * 9 = 36 lbs, with the same pounds per square foot of everything going down. Or a grand total of 48 lbs over the whole lawn. OK, the math is done, we now return you to your normal schedule. In this one particular instance, you're planning on overseeding so I'm hearing that you have a weak lawn. Consequently, I'm going really high on this schedule. If you don't have a lot of bluegrass this schedule's a bit aggressive and I noted that below May 15: Apply 4 lbs per thousand square feet August 15: Use Starter Fertilizer instead to prepare for your overseeding (this isn't critical and you can use the other stuff instead if you like) September 15: Apply 4 lbs per thousand (skip if you don't have bluegrass) October 15: Same November 15: Apply either 4/thousand or use Winterizer at the correct rate (which you'll calculate) That's 5 lbs N for the year (very high), 1 lb phosphorus (more than enough) and 1 lb potassium (a bit trim, but still OK with your readings). Normally I'd never cut the September feed, but with seeding the August one will have to do. If you skip seeding and don't have bluegrass, skip August instead. Is that enough variables for you? ;-) If it's too confusing, let me know what type of grass you have and I'll take another shot at it.

Best - great memory! That is yet to be seen, as those problem spots browned faster in the hot summer sun - so far so good though. Vicki - I did reseed with compost the year I started, which filled in a lot of the bare/crabgrass spots I inherited from the previous owner. The best weed prevention is more grass! Having said that, the key to CGM is 1) timing & 2) lay it on heavy. I'm sure someone can chime in with more precise temperatures, but I believe most (weed) seeds germinate when the soil temps hit around 65F. Since CGM (I use Blue Seal brand) seems to resist being washed away better than the more soluble synthetics I've tried, I put it down as soon as the air temp hits 60F. Last year, it was Feb! This year I put it down in April, right before that big rain storm we had (since you appear to be local). And by lay it on thick, I use 30-40 pounds per 1000 sq. feet. Due to the way organic fertilizers like CGM works, you can't over-fertilize (unless of course you totally bury your lawn with it!). I know it was the CGM (plus fairly thick, tall grass) that kept the dandelions out because I put very little on my lawn. I do CGM at 30-40 lbs / 1000 sq feet in the early spring when the air temp hits 60F and then I'll put soybean meal (also fairly high in protein) down in the fall sometime. Other than that, I mow high and water deep -that's it! Good luck and thanks for the kind words.