Reading the garden size post I got to thinking how much compost (average) do you need to properly care for a garden plot? a ton/1000 sq ft? more? less? Just trying to plan. Thanks

Most people think there is a set amount that is used per foot. But the honest to goodness truth is that no matter how much you use, you always end up looking for more.

I have three 4 foot by 20 foot raised beds and I am getting 2 yards from my really cool organic feed store. I suspect I will need another truckload. (a full sized pickup truck will hold about 2 yards of soil, mulch, compost, etc.)I have heavy clay and want to SERIOUSLY change that!

Jack

How much you need depends on how much you have. If you check for humus levels in your soil and find none you will need to get enough to bring the level of Organic Matter in your soil to around 5 percent. If your soil already has 3 percent humus you need much less OM.
5 percent is a target to work toward, a bit more won't hurt, but a bit less can.

I dump one large heaping wheelbarrow on each of my 3'-4' X 12' beds and that gives me about a 1" layer on top. I don't do more than that since I never have enough compost. I add a few other soil amendments and fertilize. I guess that would be about 8-10 cubic feet of compost per 40-50 square feet of garden surface area. But, as others have said, if you have serious soil problems you are trying to correct, you will need LOTS.

Jack, I have heavy clay soil, too, and if you can get a load of granite sand (which has a 10-year source of minerals) or creek sand (no salt), about 1/2 to 1 inch over everything, work it in, you will be amazed at how improved the tilth of your soil is

barefoot, if you keep a constant 3-inch fluffy layer of compost and leaves over it that should do it. Here's a nice conversion chart that helps:

http://www.dirtworks.net/Mulches.html

If you have no organic matter in your soil now you will need to start with a minimum of 4 cubic feet of OM per 16 square feet of garden space. About 8 inches of OM worked into the top 8 inches of your soil. If you have a residual humus level of about 5 percent an inch of compost each year may be enough to keep it there, but I put down about 1/2 inch of compost and 6 to 8 inches of shredded leaves each fall and find that by the end of August I need more and the residual humus level in the soil stays around 6 pecent.

Thank you all for your help, this gives me tons (sorry pun intended) to work with.

So how do you figure out what percentage of OM you have at any given time? Soil test? Seems like a lot of soil tests to keep track of it as closely as you are kimmsr. I am just wondering.

Jason

I pray I never end up living where the soil has to be amended so drastically! :_| I wouldn't have time to be ambitious enough to fix it.

I was reading in the paper the other day, our county has 7% humus as compared to the rest of the state which has 4-5%.

So I thank my lucky stars I am where I am.

Numerous times here I have described a simple test that will tell you the level of humus, residual level of organic matter, in your soil, but here is is again.
Sample your soil in several places and mix that all together removing any large lumps of stuff such as stone and chunks of wood.
Put 4 inches of this into a clear 1 quart jar with a tight fitting lid and fill that jar with water. Replace the lid, tightly, and shake the jar vigorously then set it aside for 24 hours. The soil in that jar wil settle out with the largest and heaviest soil particles on the bottom and the samllest and lightest on top. A good loam will show about 1-3/4 inches of sand on the bottom, about 1 inch of silt above that, about 1 inch of clay above that and about 1/4 inch of organic matter on top.
What is on top is the most important part of what you want to know and anything less than 1/4 inch or about 5 percent OM (divide that number by 4 to get the percentage) is not good.

> Jack, I have heavy clay soil, too, and if you can get
> a load of granite sand (which has a 10-year source of
> minerals) or creek sand (no salt), about 1/2 to 1
> inch over everything, work it in, you will be amazed
> at how improved the tilth of your soil is

What about greensand? is that granite sand?

Jack
Zone 6
SW Ohio

Iowa at one time had that much but mostly since no one has added much since the prairie grass was plowed under the soil bacteria have digested what was there by now. The Natural Resources Conservation Service doesn't find that much OM in Iowa soils.