The perimeter of the house where I did the new fence contains a 25m length from the back of the garage to the corner of the garden. That’s why it took me a while to do the fence a couple of years ago. Anyway, of that 25m length, 5m is behind the back of the garage and 8m or so is behind the planting beds round the lawn. The other is a straight run of fence that is pretty much all you can see from that part of the patio. We decided that we should break it up a bit by adding another planting bed. Indeed, we decided to make this the biggest of the planting beds, running a length of about 2.5m.
It’s a very simple rectangular bed that runs along the fence line.
For the base I had the advantage of being able to use the existing row of big concrete blocks they lay along the perimeter. There was nothing wrong with these and they formed a nice straight and solid edge. I only had to dig a trench for a three-sided concrete base then, which I took down to a similar depth to the concrete blocks.
As with the other beds, I didn’t put a concrete bed across the whole base, as that would mean having to find somewhere to send excess water, so what I’m actually doing is digging some of the clay out and refilling the bottoms with gravel, so they act as a bit of a sump for rainwater. We’ve never really had an issue with rainwater escaping from the soil, patio or beds before, so I made the decision that so long as we had some gravel soakaways to take water off the patio and didn’t put the slabs right up to the edge of the house then it would be fine. It would be better than it used to be, anyway. I made the mistake of not planning to do this from the offset, which means there’s been some retro-fitting of gaps in the mortar joints to allow the water in. The water that gets trapped in this bed ever so slowly seeps below ground level under next door’s path. If it comes down like stair rods for any length of time then it flows around the bed and straight over the edge, but it always used to do that anyway. The neighbour has a block-paved path along the edge, which has quite a good capacity for absorbing excess water. There’s a big gravel soakaway under there somewhere too.
Back at the plot, this larger bed might become either the “desert” bed or the ericaceous one. Whatever goes into it, there will be a lot of it.