Depends on the hay--you are likely to bring in a lot of weed seeds and certain to bring in a lot of grass seeds with hay.

That said, a nice thick layer of free mulch of any type does wonders for the clay soil you describe. It may have more advantages than dissadvantages.

I've been using a permanent mulch system in my acre market garden for several years and it works great. Talk to professional maintenance gardeners in your area and see if they will bring you their clippings and leaves. This would not be a one-time arrangement--the gardener would bring them on a daily or weekly basis forever. You just keep shoveling them on. Hay, particularly straw, is bad news in a way other than weeds--the carbon/nitrogen ratio is unfavorable and nitrogen will tie up [contrary to previous thought about mulching]. Grass clippings are ideal.

The permanent mulch system really works: Just keep shoveling mulch, plant what you like and contribute what you don't like to your permanent mulch system by cutting it out.

Happy gardening, Locust . . .

John

flowermanoat: I don't understand how that could be true about straw being such a bad mulch. If that were so, why would it be used so extensively when seeding grass, or how can you explain how Ruth Stout's methods or Lasagna gardening methods are so successful? Not being contentious, really curious... Please expand.

I did put hay in my back yard, and it seems to have only slowed the grass down. I had only put 4-5" though. Maybe I'll need to order another 10-20 bales...
Cheers,

Alaina

Two problems with permanent mulch method: soil takes forever to warm up in spring--can really shorten growing season--and SLUGS, which love it under all that mulch!

Slugs love acid conditions. Before you mulch, scatter ashes and/or lime. Slugs hate both.

I mulch with heavy cardboard and straw, over mowed grass/weeds, with ashes and/or lime under the cardboard, as my soil is acidic. So far (fingers & toes crossed), I have not had much of a slug problem. This is an on-going experiment for me, as is the rest of my gardening.

Sue

Hi - I am late on this question, so I wish the writer would comment again since it has been 6 mo. or so since the original question. You are a lot warmer and wetter and have acid? soil, whereas here I am gardening on loamy sand, 5-7" of yearly precip, and alkaline (7.5) soil. I am interested in knowing what the result of your deep hay mulch has been. I have been using hay in that manner here with, I believe, good result. We have few problems here with slugs, but I agree with one of the commentators that late warming if the soil in Spring is a drawback. I pull the hay back to seed, and then replace it after 2nd leaves appear or I put transplants in. I basically concur with the Ruth Stout methods. Dirtgal in Wyo. Z 4b