Hopefully someone with lime experience will give you an authoritative answer, but off hand, 40 pounds seems like twice as much as you need at one time. I would split the amount for spring and fall. Lets say you have 2,000 square feet to cover at 20 pounds per 1,000. Lime comes in 40 pound bags so you'll use the entire bag to cover the 2,000 square feet. Start with 10 pounds of lime in the spreader and the setting mostly closed off. Then run over the lawn and see how you did. If you ran out of lime early, then estimate how many square feet you covered and how much is remaining. If you covered exactly 1/4 of the lawn, then the setting is exactly right. If you went over less than 1/4 of the lawn, then you need to close it off more. If you went over the entire lawn and had some left over, then you can open up the spreader to allow more to flow out. This is a trial and error method, but it is better than totally guessing. Estimate how much you have left over in the hopper and guess at a different setting. Once you have that setting, write it on the bag or somewhere in the garage so you can remember it for the fall.

I would not sweat the fertilizer ratios. Just get sort of in the ballpark and follow the rate listed on the bag for your spreader model.

Thanks, dchall. That was actually very helpful. It makes perfect sense, and I hadn't read that tip in any of the lawn books that I read.

Thanks, dchall. That was actually very helpful. It makes perfect sense, and I hadn't read that tip in any of the lawn books that I read.

You're going to end up "eyeballing" the settings, but at least you will be helping inform yourself by experimenting a little. I tried doing this to apply 15 pounds per 1,000 square feet of corn gluten meal several years ago. I ended up with the setting all the way open and going over the area twice to get it all down at the right rate.

My next questions were going to be about aeration. But reading your past posts, I guess I will try the shampoo method. It sounds less scary than hiring somebody to punch holes all over my lawn and if it doesn't work. Now I just have to google what a "hose-end" sprayer is, lol.