[10dahlia]

could you tell me what depth of soil is good to grow veg in raised beds

[Elcie]

It depends on quite a few things really, including what type of soil you have.  When I first got my allotment I literally just built the wood around the soil so there wasn't really that much about them that was raised!  Mind you over the couple of years they have grown in height as I have added compost and rotted manure to them.

[FERDY]

I say the deeper the better mine are 20cm.

[kermit]

Mine are almost 2 feet!  But we basically had zero drainage and wanted them to look good in our garden.  They are only half full, this being our 2nd year, but even 12 months of compost, good quality top soil and manure, and the soil is looking lovely.  A good foot of it.

[Dominic]

As high as you want really.
If you want them to look good in the garden they could be brick and waist height.
If you just want them to be easily distinguishable from the paths they could be 5cm high.
Or anything in between.

[mumofstig]

IMO Unless you have problem soil, the wood is only to mark where the beds are and to keep you off the dug soil.
AS already posted digging deeply at the start will raise the level by a few inches, and you can add some of the soil from the pathways. Also, each year as you add manure or your own compost the level will gradually rise further. This way your 'depth of soil' includes the soil under your bed as well as that retained by the boards.

Of course if you are growing in beds over concrete, it's a different question with a different answer  

[eddie]

Mine are about 8" most important is good drainage

[Ice]

It's horses for courses as far as this goes.  You need to decide why you want them in the first place.  Is there a particular problem with the soil?  Do you need a "no dig" system because digging is difficult or you just like a formal structure?

There is no "wrong"answer, it's your garden and it's your decision.

[Aunt Sally]

I'm about to build one for my salad crops.  I'm making it 16" deep so that I can sit on a chair to tend it.

I will be ringing the top with copper to keep the slugs off.

[10dahlia]

any suggestions for raised beds situated over concrete?

[Trillium]

Check this link for beds over concrete. On the left side of the homepage, go down to the 3rd video - raised beds in the city. I know she's doing this one over concrete but I can't find a more direct link to it.

http://www.gardengirltv.com/lawns_and_edible_landscapes_blueberries_planting_strawberries_city_orchands.html

[markp76]

Sorry to hi jack this thread but noticed Aunt Sally saying shes going to ring the top of her raised beds with copper to deter the slugs, how does this work and are we talking copper piping or something totally different?

[Trillium]

Not piping. It would be thin, narrow strips of copper tacked to either the underside of the top edge or right on the top edge (users preference).
Some folk who have used the strips find it doesn't work well, while others swear by it.

[shokkyy]

any suggestions for raised beds situated over concrete?

I have an area of old broken up concrete in my garden and I wanted to use the space for veggie plots. It would have been a huge task to shift all that concrete so instead I decided to leave it there and put raised beds on top. Because the concrete is old and broken the drainage seems to be absolutely fine. I used 4' X 8' X 6" decking planks so the beds are just 6" deep. I put weed suppressing fabric at the bottom before the top soil. Obviously you wouldn't be able to grow anything too deep rooted in there, but I've had some very good crops of strawberries, peas, beans, carrots (the round sort), courgettes, tomatoes, cucumbers, onions, garlics, shallots, celery and all the salad crops. Anything that would work in a grobag would be fine in that depth of soil but if you want to do deeper rooted crops you'd obviously need to build them higher. What did surprise me was the amount of top soil I needed to fill just four of these beds