I was going to get the really cheap compost we get from the RI recovery corp and mix it with bagged topsoil but could not figure out the whole renting a truck etc for the minimum 1 cubic yard they were ready to sell. So I got the organic garden soil from miracle grow. I realize now that I can't just fill it up it needs to be mixed with native soil. The native soil isn't that good at depth and I was told the soil in our area is clay. Also the point was to have about 8 inch raised bed so the 50:50 or 1/6:1/3 ratio of native and garden soil isn't going to raise it to 8 inch. (the bed isn't much big - Just 4X3 or 4X2 adjacent to the fence)

So the question is, will it be useful to get some topsoil and some bagged compost and mix it all up, that is, topmost layer of native soil - aboutt 3-6 inch, garden soil and the bagged top soil and compost? Or is there a way to layer it? or is this all wrong and I need to start over?

If I use all garden soil is it going to retain too much water? It is also going to end up way too expensive but this season I will live with it may be.

For our area I was planning to put the plants out by June 1. Hopefully if I can get my raised bed together in a couple days, I can still keep up to my timetable.

Thanks for any help.

Did you try your local nursery for topsoil or compost? It could be they would deliver it for less than you'd spend for bagged garden soil and it might be better, too.

Mix in some of that Evergreen Topsoil (I don't know how they can get away with calling it topsoil) at Lowes .. it runs about $1.35 a bag and I cut my ProMix with it 50 50 .. works out great.

Bagged compost is reasonably priced, too. For in-ground plantings I just mix compost in with the native soil (mine is clay, too) at planting time. In a raised bed situation you can do the mixing together ahead of planting time; just don't forget to mulch. That newly perfect space will be a magnet for weed seeds otherwise, and they always grow faster than our desired plantings.

For the most part, a raised bed is a space whose planting medium is fluffy and loosened -hence raised. When you dump in topsoil, compost or other materials you're in effect just emulating what could also be done simply by digging up and loosening your native soil. Adding compost will help it drain away excess water, while also helping to retain water during dry times. The sides of the bed are simply there to keep your loose growing medium and mulch from washing away in a heavy downpour.

So don't over-think it. Keep it as simple as possible for your situation. If you can't dig your soil at all go with more new medium by volume than you would if you could dig. If you can dig your native soil (a day or two after a good rainfall is a good time to check for this ), you could just mix in compost and plant.

chelle said:Bagged compost is reasonably priced, too. For in-ground plantings I just mix compost in with the native soil (mine is clay, too) ...

... When you dump in topsoil, compost or other materials you're in effect just emulating what could also be done simply by digging up and loosening your native soil.

I agree with Chelle. Clay is actually one of the most valuable parts of good soil. It's only a problem if you have too much soft, sticky clay and not enough open space (pores, voids, air channels, gaps).

Improve the top layers your own clay soil with compost, plus maybe amendments like ground bark or peat moss. Fine bark mulch (preferably conifer bark like pine, fir, balsam or hemlock) will be much cheaper than peat moss, and probably cheaper than ground, screened bark. The idea of using bark in addition to compost is that it is coarser (bigger chunks aid drainage and aeration) and lasts longer. It breaks down over 2-3 years and releases organic matter just like compost. But meanwhile it helps provide structure due to coarseness.

I also think (just my theory) that after you mix fine bark fibers with clay, the clay "soaks into" clods of bark fibers, and the fibers and bark dust mix with clay to produce something less sticky and less inclined to leach out and flow into every little crevice and air gap you were trying to create.

If you amend the deeper layers a little, and the top layers a lot, you can create a gradual transition from airy, fluffy loam in the top 6 inches, to "OK" soil for another few inches, then barely-improved underlying soil and sub-soil. The improved deep aeration and loosening encourages and allows roots and worms to go deeper to find water and nutrients.

This makes your root zone a little deeper than the bed itself in the first year.

During that year, water and nutrients and roots and worms will penetrate even deeper, and loosen and enrich deeper sub-soil. Next spring, your root zone will start out extra-deep, and grow even deeper each year (without you digging). Just keep top-feeding with more compost and mulch. Decomposing compost leaches down and keeps the deeper soil fed.

If the soil has a fairly gradual transition as it goes deeper, water won't pool until it hits really deep sub-soil with SO much clay that it won't drain at all. Then water has to drain horizontally until it finds an exit. (If your impermeable clay layer was so near the surface to make that a problem, you would already have seen flooding problems and runoff during heavy rains.)

Thank you very much for all the comments. The native soil in the area is clay, I was told but it is not supremely so. In many spots it feels like white cementy soil as if the owner filled it with construction material. So depending on that I have zeroed down on two small patches where I can build up a bit but can use mostly the native soil and amend it.

Happy gardening, Bhingri.

I'm right there with you on the raised bed building...I have a few more to do myself this year. Mine are going in on hot, dry slopes, so I'm using a form of hugelkulture for those. The first link below is of one I built last year in a shadier area.

The thread "New addition to an existing bed" in Permaculture forum

Love these beds...they'll hold so much stuff, and do it so well.

It sounds good! Good luck.

>> two small patches where I can build up a bit but can use mostly the native soil and amend it.

I think that's smart. Focus on a small area at first, and learn what works best or is the easiest. Don't rush or burn yourself out.

Expand next year or at leisure. Acquire compost when it's convenient. Decide what amendments work best with your light clay. Maybe figure out whether the white cementy soil really is construction material or bad for plants, or whether it is a sandy subsoil that would greatly improve your clay if you mixed 20-30% white stuff with 70-80% clay and then amended that with compost.

Maybe plant a few delicate plants in 50% white stuff mixed well with 50% clay, then see whether they die or thrive.

Definitely agree with Chelle, "keep it simple." For your first year, use some of your own soil, mix in some bagged garden soil and compost -- it won't be perfect the first year. Collect leaves, grass clippings, etc. for compost to add to your raised beds. Maybe use some grass clippings or straw for mulching your plants, which will then be incorporated into the soil over time. I don't use raised beds, but when I started my garden at my present location (over 20 years ago now, which is hard for me to comprehend) the soil was very heavy, every time it rained there was standing water in the garden, very few worms, and so on. Over those 20 years we have not only added a LOT of organic material (we bag our grass clippings and use for mulch, use the excess and other stuff for a compost pile) and also added quite a bit of sand to our soil (not a recommended practice, but it worked for us), as well as removing what must have been at least a ton of rocks (thanks to the ice age glaciers) and now have some pretty darned good soil going. Don't worry, it won't necessarily take you 20 years -- but really, you can grow a pretty good garden in whatever soil you have to work with. For instance, when planting tomatoes you can add some "good soil" or compost or whatever to the individual holes. Every year it will be better...

Don't forget to use some sort of fertilizer!