I also have clay. When I turn over the clay and amend with manure, or sometimes peat and sand the bed will raise 8 or so inches. I will usually dig in amendments twice. On each pass I turn the ground over in opposite directions to help break up the clay and the sod which I leave in. Some say to get rid of the sod, which is where your best soil is. I treat my existing sod, on a new bed, as tho it were a cover crop.

If you need a 2 foot high bed is one thing but for the 4-6" you're talking about I'd suggest just digging in some amendments. You'll get the same drainage improvement without the framing time and cost.

If you want free manure google horse boarding with you town in the search phrase. They're everywhere, even near NY City. A farmer might till in his manure; but the horse boarders are just glad to get rid of it. An alternative is mushroom manure which you can get delivered. I paid $39 a cubic yard and delivery was $35. I'd suggest you dig in three inches of the manures and also some chopped leafs, or compost. I've dug in whole oak leaves which will disappear by next spring, but they're hard to dig thru.

I dug in 4 inches of horse manure into my potato patch last fall and 4 inches of mushroom manure into my tomato patch last spring. That was too much, the tomatoes were too tall and ripened late. The potatoes were fine except that the stems were 5 foot long.

I don't recommend adding manure in the same year for root crops or leafy crops that'll get splashed. However if you amend your soil this fall for next year you'll be fine. That's what I do and don't have a problem, even with my suppressed immune system.

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For perennials don't dig in amendments. I'd suggest you just mulch with mushroom manure or compost, or hardwood bark. Don't mulch with horse manure as you're inviting a lot of weeds. You can lightly fork that in, but don't dig.

A few years ago I did exactly as Gardengal suggests, and it worked like a charm! I disturbed the clay under the grass with a pitchfork, put down newspapers, and piled on my soil, a mixture of black top soil and manure. The next year I planted my perennials, and they immediately took off. I did it in November, I think, and at that time also planted some cheap bulbs at 80% off. They all came up too. No grass grew up through the newspaper at all.

Thanks for the tips! I was hoping that the late date would mean not having to worry about grass growing through, but since I've just gotten started, I can use some old newspapers on the rest of the spaces. Do you think I could plant my perennials THIS fall? Several potted one from end-of-season sales. I figure that they'll fit nicely in 6" of soil, set up a bit of root, then die down for the winter. By spring, hopefully all will be well!

Should be fine, I would think.

I have planted like that in a new bed, but you'll want to be sure the roots are deep enough that they can't heave out of the fresh new soil and freeze. Mulching would help. The plants should come through fine.

Agreed.

"garden soil", is that a bagged product or a bulk mixture of soil and compost? Reason I ask is that a lot of the bagged garden soil products seem to be all organic matter, and if you're mixing that with compost, you won't have much of the permanent mineral soil component. Organic matter will shrink as it continues to decompose, so your raised bed will not be very raised after a year or two. OTOH if you bought a truckload of soil/compost mix it will probably be fine.

In this area if you buy topsoil what you get is clay mixed with some sand and shredded. No organic matter. My neighbor built an addition and when done tried to replant a lot of grass. He bought "topsoil". I suggested he mix in mushroom manure, he didn't. In the fall he hired a landscaper to redo it. The landscaper added more of the same "dirt". At least he covered the seed bed with the mushroom manure.

My new potato bed which I amended last fall and planted potatoes in the spring is still raised up about 6 inches. And I need to add maybe another inch of mushroom manure and some semi-chopped leafs for next year.

What I'm using is a bulk mixture of 50% topsoil and 50% compost. I'm not really looking to make raised beds, though. I'm counting on some shrinkage by spring for sure! The roots of these potted perennials would be maybe 1" above the clay soil line. I'm hoping that rain, snow, and the thaw/freeze cycle in late winter will help incorporate that good soil, so it will be easier for the roots to pierce in the spring.

OK then. I too think it would be better to break up the existing surface at least, but it won't be the end of the world if you don't, and your mix sounds fine.

I was actually just laying in bed this morning, thinking the same thing. Do a little tilling, add another couple of inches of the mix, and get the plants in the ground. We're getting into the low 40s at night but still up to the 70s by day, but that can't last much longer. Wow, it takes a lot longer to shovel an entire dump truck load of compost than I thought it would! ;)

I used to be able to shovel and spread a cu yard per hour. Now it's a yard per day. My opinion: if you're tilling the ground you don't really need to till in anything but the compost.Those plants will do better in the ground. I think! We don't know what you're planting and where.

I've decided to do part till (where I'm going to stick this year's perennials), part cardboard (over really grassy areas), and part "just pile on the compost" (where I've run out of motivation). I guess I'll see next year which was the better choice! :)

I've expanded some of my beds using lasagna methods in my loamy clay. It worked wonderful. Lots of earth worms. One year I started in the fall. I collected material for a month or so. grass clippings, chopped leaves, cardboard, kitchen scraps which I buried deep in the pile. Just cut the lawn short, layer over cardboard and soak it and then just layer the materials until you run out. I can't remember if I added some bagged organic compost to the top or not. Then a layer of combined chopped leaves and grass clippings as a mulch. By spring it was ready to plant.