You could use the stuff you were planning to use at a higher rate than what they're recommending. I'd use about 15 lbs per 1000 sq ft. You'll be applying a little less of the P and K, but if you mulch mow, those will stick around.

How does that work? is it the ratios between the three that is important or the number itself? Do I put down 15 lbs of 7-3-2 each month? If this is true then I would need 450 lbs of fertilizer. Oh the postman is going to love me (not!).

The ratios are important, but what I'm saying is that I think you can use less P and K than they recommended, assuming you're mulch mowing, because it will stick around, but the N goes away faster.

The way I decide how much fertilizer to use is to calculate the amount of fertilizer it would take to get 1 lb of N per 1000 sq ft (ignoring the P and K). The recommendations you got were for a little more than that, but I don't like to use much more than 1 lb per 1k sq ft at a time. If you have 7-x-x, to get the amount you need for a pound of N, divide 100 by 7. That actually gives just over 14.25 lbs, but I find it easier to round to the nearest 5 in most cases.

They're saying you should fertilize 3 times. If you've got 10,000 sq ft, that would amount to 450 lbs of fertilizer.

If you're buying this and having it delivered in the mail, I'd be less concerned about the postman and more concerned about the cost.

You might want to take a different approach and get something you can buy locally. If you're trying to use organics, many people use grains like soybean meal. Another one that people use a lot is alfalfa. I use coffee grounds from Starbucks, but I don't think that would be very practical on a 10k sq ft lawn.

You're overlooking what the test is telling you, and concentrating on the fertilizer instead.

Your lawn hasn't enough fertilizer. It is starving. I'll bet it looks it, in hot weather, other than within thirty days of you putting down your organic stuff.

The organic stuff is fine: it is especially fine in the summer, when the lawn needs a snack, to do it's best. You are a very nice person. If I showed up at your place, and we worked half a day, you'd likely provide a little snack. Say some potato chips and a beer, (plenty of salt, eh?) and it would be very much appreciated.

There's a time and place for everything. Including gluttony. (You thought I was going to say 'moderation' didn't you? No, you are a moderate person. You need to learn about gluttony).

If I showed up instead, at your place for Thanksgiving, a traditional feast, I'll be very upset if you offer me some chips and a beer. I want BIG FOOD, don't I? I want piles of turkey, scoops (yes more than one) of dressing, I want a huge bowl of mashed potatos, and I want big, rich, buttery gravy all over everything. And some bread. And pass the butter, please.

Your lawn has missed the last four Thanksgivings, because you're offering it these little snacks. In the fall of the year, you should put down two, about five weeks apart, big, really BIG, feedings. You haven't done it, and I can prove it: read your test results.

This year, I want you to put down the biggest first number fertilizer you can, with smaller second and third numbers. Smaller, but not approaching zero, second and third numbers. Something like 24-8-8 would be better than 20-2-4. Put it down twice. September 15, and October 20th to 30th.

You, and only you (this is a one time shot, based on test results) will do it again, between May 10th and May 20th.

Then, come summer, the lawn will love a little snack. And you are quite right to offer it. One in June, none in July, and one in August, the first half of August. (Because we don't want it too close to the September feast, do we?)

Next year, we will do the two heavy fall feedings, and the following spring turn the May feeding into a snack.

Somewhere in the next two years, you will write back, and let us know how we're doing, please. My guess is that you'll see some dramatic results. Keep us advised.

philes, thats one of the best posts I've read in a while. Thanks for taking the time to explain your point of view. Helps us newbies a lot.