Raised beds - best method of construction?

SandT · February 2017

Hello

tomorrow, we plan to build raised beds either side of our garden for plants. Each one will be a run 5.2m long X 30cm high and 40cm deep & made from treated sleepers. As they will be positioned with their back against the new fence, we would love your advice on the best way to construct them:

Do we use brackets and fix them to the existing concrete-set 3" posts, or do we set them against their own 2" concrete-set posts?

Do we do it 'properly' or will the fence posts be the best anchor?

Kitty 2 · February 2017

I don't see the need to fix them to the fence posts SandT.

It sounds like you're building them long and low from heavy sleepers. Should be fine simply sitting on the ground. Are you trying to prevent them from moving?

Or am I missing something?

Fairygirl · February 2017

Assuming the fence is yours and is substantial, you could use a metal corner bracket to connect them to the fence, but I'd agree with Kitty - there's no need if you're using sleepers to that height.

I'm also assuming you're laying them on top of each other so it would only be a couple of sleepers high. If you arrange them 'brick style' at the corners so that they overlap, there's no need for any corner posts either You could lay them directly on top of each other without the overlap, so you'd have a gap at the corners. If you do that, a small corner post (some 2"x2") will keep them neat and tidy and prevent soil and water loss there. You wouldn't need to concrete them in though, as it would simply do the same job as the corner brackets.

SandT · February 2017

Yes, the fence is ours and recently built.

The gravel boards were removed when we had it built, which is why we were thinking the back of the beds would become the new gravel board.

If we just placed them on the ground, will plants and soil not pull the beds forward and risk it collapsing over time? I suppose this is why we were thinking of setting some vertical posts in concrete.

Kitty 2 · February 2017

The sleepers shouldn't tip over if the ground is level. A 5 metre run only a foot high would have a substantial weight to it I'm guessing.

Why no gravel boards? They keep the fencing clear of the ground to prevent rot. Are they standard panels or a bespoke construction?

Do you have a photo? It may help understand the problem.

Fairygirl · February 2017

I still don't see why you'd need posts set in concrete either, unless you're intending planting a lot of very big shrubs or something. If you are, beds of that dimension probably aren't going to be adequate anyway.

If you're planting on a slope, the beds should be built so that they're horizontal anyway. They won't look right otherwise.

As Kitty says, a photo would help.

Think the beds are to be 5 metres long, Kitty - not five foot, but I'm assuming the sleepers will be joined to each other with timber or metal struts at the back, and also have something joining them (timber battens) at right angles, to the backs of the beds as well at various intervals.....

hogweed · February 2017

As you will only have two sleepers high you should be fine. Unless you were thinking of laying them on the high side rather than the flat side. In which case I would 'peg' them down at the corners and joints. But I would just drive 3x3 posts into the ground - no concrete- and screw in.

Kitty 2 · February 2017

Get ye to specsavers Fairy . I said 5m long x 1ft high

30cm is a foot, yes? I'm getting confused

Your method of construction sounds right?.

Love your raised beds by the way, fab planting and colour theme

Fairygirl · February 2017

Kitty

Yes - 30cm is a foot - whatever school you went to

It's like timber merchants and builders - all the wood's 2.4 metres, 3.6 metres in length, and 100mm or 150mmm width etc, but then you get 2 by 2 which is inches....

Numpties

Did you mean my raised beds or is there a photo of the OP's that I've missed too?

Last edited: 25 February 2017 14:34:08

SandT · February 2017

Here are some photos from when I was levelling the ground. I'm afraid I don't know why they always get posted at an angle – please don't get a sore neck! The fence is made from treated pine and was bespoke. I think the fence builder forgot to replace the gravel boards afterwards, but my husband thinks they don't need replacing if we are putting raised beds against them(?)

Beds will run from the front of the photo to where the rake is - on either side.

Kitty 2 · February 2017

That's looking good SandT, I like your fencing .

The ground is nice and level, I see no need to fix the sleepers to the fence posts. I'd build the beds as Fairy described and butt them up to the fence.

I wouldn't worry about the gravel boards (after seeing it), it's fence panels sitting directly on the soil I was concerned about. You have a gap keeping them clear of the ground.

Looks like an exciting project, I hope you keep us updated on your progress. There are plenty of helpful gardeners here on the forum who can advise on allsorts.

Fairy: Yes it was your beds . The ones in front of the black fence, with a planter on the top. Lovely lush greens with purple and white flowers. Gravel path in front.

Think I saw it last year? That was yours wasn't it??

Raised beds - best method of construction?

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