Would you.....

[Rosee]

...build raised beds ontop of concrete? Will I have drainage issues? Thanks!x

[Spunky]

...build raised beds ontop of concrete? Will I have drainage issues? Thanks!x

No expert Rosee but could you put drainage holes in the bottom sides of what you're using for the beds and treat it like a pot or see if you can drill into the concrete to make holes for drainage

[Potstubsdustbins]

If its ordinary exterior concrete the yes you can, no problem with drainage. Concrete is not usually smooth enough to cause any issue's.

Potty

[binley100]

They'd have to be pretty deep for root veg tho' ....

[bretty666]

Hi. im...........a concrete.......specialist? Any outdoor concrete is going to be at least an xc1 c25/30 therefore will only be surface porouse up to 2cm maxi but, should have a slight slope on it anyway. i would advise you put a 3cm gravel bed at the bottom of your raised bed covered in a membrane like geotex or another porouse membrane or very close weave to stop the soil clogging the gravel up ...but as previously stated its going to need to be pretty deep for root veg. as for drilling into it , i would advise against as most concrete has reinforcement bars in it which would rust and you could end up with cracked convcrete as the water would rust the re-bars in the concrete. so... put a spirit level on the concrete, find out whoch way your slope is then make your bed and drill a few holes in the lowest side.of the wooden frame at ground level then put in sone gravel then membrane but not water proof then soil. that is how i would go about it.

[Rosee]

You're all awesome, thank you for the advice. How deep would you say I need to be for root veg? I don't think I plan on growing any in there but if I go deep enough it'll always be an option x

[alldigging]

http://www.carryongardening.org.uk/f...inal_Nov08.pdf

Using paving slabs maybe.

[Hayley]

Hi Rosee my garden is mostly concrete and I made a few 6x3ft raised beds late last year. From what I read they need to be at least 1ft deep if there going on concrete. I know I'll never get parsnips as big as people who grow them in the ground but any is better than none.

Here's one of my beds, sorry it's a bit untidy at the minute.

[gardening_gal]

I have 25cm raised beds on hardstanding. Things grow well in them, but they just are not high enough for the likes of carrots.

I'd be aiming for at least a foot as Hayley said above, but maybe even a tad higher to be sure.

I can stack my beds so I have one on top of the other which gives me a depth of 50cm for root veg. That's too high tbh but it's either too shallow or too deep. I keep saying I will build one with a 35/40cm height but I've not done it yet.