Flower bed on concrete ?!

[MelanieWiggles]

We built a kitchen extension earlier this year, which juts out into the garden leaving us with a side return. We got the builder to pave this over and build a small raised bed at the wall (about 9 inches high and 1.5 ft wide) to allow us to plant some climbers to train over the wall and some small / medium height flowers. The look we were going for was something like this.

I went to start planting it yesterday and discovered the builder has built it on the old concrete patio. I am absolutely livid.

The builder will be back in December to do the final snag so worst case I can make him dig it up, but it will be a big row and I can't see how they can get rid of concrete now without a jackhammer, which means they will probably destroy the new patio.

If we leave it as it is, will we be able to plant anything substantial it it ? If filled to the brim we will have a maximum of 9 inches of soil, and I presume no drainage (although the end of it is built on soil as the new patio is longer than the old). Am I freaking out over nothing ?

[Blackpuddingbertha]

I would speak to the builder and see what he suggests. It may be possible to add some additional drainage and build it higher to give more depth, but that may prove just as tricky as digging through the original concrete.

[WF]

Okay, we had beds over concrete for a long time. They were 18 inches wide by about 18 inches deep. I filled them with really good compost. Everything grew fine. You do have to feed though as like with any other container. Re- drainage, stick pebbles, stones, old broken crocks in the bottom, drill the occasional hole through where the bricks are mortared (near the bottom) and this will allow water to drain.

[WF]

9 inches of soil isn't a huge amount, however. They will need much watering in summer so you need to think about drought resistant plants (I'd mulch so water doesn't evaporate too much).

[Earthworms]

I don't think it's too bad. As long as they are drained ( couple of holes in the brick) and you treat them as a container then you should be fine.

In my last house i had a whole bloody Flower bed that some silly bugger had made by putting 5 inches of crap topsoil over a Tarmac drive.


I managed to grow all sorts, even veg - just not potatoes


As long as you are aware of it, and plant with something drought tolerant like lavender if tou know you won't get round to watering regularly I think it should be fine.

[MelanieWiggles]

Thanks everyone - have calmed down by now and see that I can probably make something out of it. I appreciate all the advice.

Am still going to have a go at the builder though !

[yomellamoHelly]

We had several of these in our current house. Everything in them was dead. Only discovered reason on digging them over. All now gone and lovely fresh, unfettered soil instead.
Same in old house. Max. 9 inches over hard landscaping. Everything looking very sorry for itself. Also all got excavated out to get a proper garden.

I would want it jack-hammering out personally.
HSS Hire shop near s has deals on every now and then and have been able to hire one for £38, IIRC. Would expect builder to have his own. So not end of world.

Only question is what's under the old patio. Could be a can of worms you'd rather not go near.

[loraflora]

I have cobblestones in my front garden with a couple of planting gaps for shrubs and wanted full plant coverage, but was too skint to get them removed at the time. Didn't know you could hire something to get rid. I decided to put down a thin layer of soil on top of it and planted sedums initially, but when I got bored of those added thuggish plants like red valerian and vinca. It's well established after a few years and the soil is maybe 3 inches thick at best! also had libertia, violet and purple toadflax turn up of their own accord. Admittedly those plants will not be everyone's cup of tea but it just goes to show that some plants - albeit a limited range - will grow almost anywhere. 9 inches doesn't sound that bad.

[wonkylegs]

We bought raised beds that were about a foot high and put them directly on the old concrete patio in our old house.
They worked very well, we had an exceptional crop of potatoes & salad leaves in one, anemones, bluebells, snowdrops, nasturtiums, and other mixed flowers in another, clematis, lupins (when the slugs didn't eat them) delphiniums, azaleas, lilies, tulips, daffs etc in a big long one.
I filled the bottom of each one with a bit of pea gravel then topped with a mix of compost & topsoil. There were a few drainage holes, and we never had a problem with drainage or it being too dry.
I top dressed it once or twice a year but otherwise they did very well, I was sad to leave them behind.