Grit is very, very small gravel. They sell it for poultry and it is cheap. Hubbie bought me some from a type of limestone to use around plants that need a higher Ph. My friends who use raised beds have very high ones so that they do not have to bend over, but I don't think they need to be that high.

My SIL wants to build raised beds for her mother (who is now 83, still gardening avidly) this spring so got 2 books off the internet. I will be over there later this morning and will TRY to remember to get the titles and then post them.

This is probably not what you want if you are doing it out of wood but my son made a small bed out of layered stone. Just wanted to share. It is in a small townhouse backyard.

{{gwi:558983}}

The 2 books are: Permanent Raised Bed Gardening, by Steve Upson, which seems to have been privately published by the Samual Robert Noble Foundation, Ardmore, OK, no date given, and Cubed Foot Gardening, by Christopher Bird, The Lyons Press, Guilford CT, a 2001 new edition of an earlier one. The first I imagine was used and would be dicey to find, but the second should still be findable.

There are instructions, if sometimes rather vague ones, in a lot of gardening books, so if you have access to them, start looking....

As far as height goes, it's up to you. If you want to sit on the edges, then a minimum of 15-18" would probably be needed, maybe higher - this would entail reinforcing the sides so they stayed straight and upright against the weight of the soil plus a person sitting.

I make "raised beds" very informally, tilling and then raking the soil up from both sides, so as to get deeper soil for the plants' roots. I can change where these are if I want, simply by tilling again. It sounds like you don't want to do that, so you can just strip off the sod, or you can cover it with 4-6 sheets of paper of flattened newpaper then add your "good" soil, which would do the same thing with a lot less effort. The grass and most weeds will be killed off this way and will add to the soil. Tough perennial weeds, like horse nettle, curly dock, greenbrier, etc., will still come up, but they probably would anyway, if you stripped the sod off - their roots go deep and sprout from pieces left behind.

You probably should go by the depth/heighth of whatever you are using for the sides, be it wood, cement blocks, sheets of metal roofing, whatever. If wood, then you will probably be using non-treated wood, so probably rough-sawn 1x6's would do for at least 5-8 years. You will need 3x3 or 4x4 pieces for blocks to attach to at the corners, cut to the appropraite lengths - again you CAN use treated, but rough-cut will probably do -although, it IS easier to replace sides than to replace the blocks.

Anyway, I hope this gives you enough to be going on with. Just be sure to leave sufficient space between your beds to get your wheelbarrow or garden tractor down btweeen the beds. And plan for how you will do your watering NOW - deciding you NEED a faucet in the middle will be much easier to do before the beds go in than after. Same for your compost pile....

@trisheff

I actually really like raised beds. I tried the regular way of gardening like I used to do when I lived in PA. when I got about an hour into manually turning the soil I had a foot tall pile of rocks and a deep hole.

I built the beds that I linked here (my first) and they lasted 5 years. I used 1/2 in plywood. I have since gone to 2 x 12 lumber. If you try the plywood method, put the support 2 x 4 about every 2 ft. If you don't, it will bow. There is quite a bit of info on the square foot gardening part of this forum. I don't have any new pics up anywhere, but I have 4 of these beds now plus smaller ones for strawberries and one for rhubarb. I would stay to about 3 or 4 ft wide for ease of picking and weeding.

I had a total of 14 tons of topsoil delivered. It has taken a few years to really build up that soil to where it is now. The bed in the photo now has the the richest soil I have ever planted in.

Here is a link that might be useful: {{gwi:558982}}

I built some raised beds for veggies using loose 6 foot fence boards because I had them left over from making a privacy fence. The boards weren't treated but lasted several years, although the wood stakes in the ground that they were fastened to didn't last as long. The boards that formed the sides of the bed were only about 5.5 inches wide so the bed wasn't that high. The first year the soil I put in was too much like the soil amendment you mix in with clay. I couldn't keep the beds watered!

What worked was mixing in some clay with cow manure and roughing up a few inches of the clay underneath. Tomatoes, melons and pole beans did well.

we built some of ours with the thickest and widest metal roof flashing we could find and spaced poles on the outside every 24" or so. foldeed down 1/2" at the edge to make it less sharp, and grommetted the ends together. we didn't want to have to rebuild them or use treated wood since i was growing edibles. since some of the beds have dwarf fruit trees- i really didn't want to have to make new sides down the rd. and we couldn't afford nor had room to to a brick or cement block type wall- it's a tight space and i wanted to maximize the amount of beds icould get in my precius sunlight. i wasn't sure how long they'd hold up, but we're on year 4 doing well. the metal dinks a little and bulges some, but it's not bad.

we tilled the soil good (in that area a nice sandy loam) before we made the beds and mixed the bottom in with the following amendments. i mixed a little homemade compost, the 'compost' you get from the landfill here in wake co, clay left from digging a pond, peat moss and whatever else i had on hand in. i used about 1/2 landfill compost to 1/4 peat moss & 1/4 clay i guess. i didn't have tons of homemmade stuff or i'd have used more. the beds are about 10" off the ground. the soil went down considerably the second year, so we mulched heavily with more landfill stuff and it's worked in very well. i think having the clay in there really helped keep it more 'dirt-y', and able to absorb water. now of course the compost is dirt, too. the beds have produced really really well. i mix in some bonemeal, espoma gardentone and lime each season before i replant the seasonal beds. i love raised beds- the only issue is when you have a drought- they are so much more thirsty than anything in the ground. good luck!

Thanks for the input and the photos. The soil here rocky/clay so it just doesn't seem like a good idea to dig into the ground much- Plus these are being put on a fairly steep slope so they need some enclosure to stop the soil from running off. I bought 16 foot long 2 foot x 12 inch untreated wood boards and had them cut into 4 foot sections. (these are for veggies) I will make a bunch of 4x4 beds- I have made beds before in california that were too big and too thirsty and they just didn't hold any moisture so thanks for the input on the clay. i also put them too close together.. live and learn. Thanks for the water placement comment- i hadn't thought about that.
Trish