Author Topic: Optimum size for raised beds.  (Read 1335 times)

George the Pigman

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Optimum size for raised beds.
« on: October 18, 2021, 18:48:50 »
Next year I am switching to raised beds on my plot (apart from the potatoes).
What are peoples opinions of the best size for raised beds?

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Optimum size for raised beds.
« on: October 18, 2021, 18:48:50 »

saddad

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Re: Optimum size for raised beds.
« Reply #1 on: October 19, 2021, 08:01:43 »
As long as you can reach the middle, which depends on your arm length, but 5' is usually OK, the length fits the space available. Try not to go beyond bout 24'.

gray1720

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Re: Optimum size for raised beds.
« Reply #2 on: October 19, 2021, 08:58:13 »
I'd agree with that - you want to be able to reach the middle from both sides without stretching too much. Height probably depends on how much soil you have to put in - any lift will make them easier to work, but obviously the taller they are the more soil you need.
My garden is smaller than your Rome, but my pilum is harder than your sternum!

IanDH

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Re: Optimum size for raised beds.
« Reply #3 on: October 19, 2021, 10:12:04 »
We went for 4' wide when we went to raised beds some time ago over heavy clay.  My back can play up and not having to stretch too far helps a lot. 

Have also gone to no-dig in the raised beds over the last 2 years as there is no need to walk on them.  Has worked well.  Good crops and fewer weeds.

We also net using a fine net to reduce/remove impact from root fly / flea beetle.  Again has proved successful.  If you look to go down this route might want to look at length as a multiple of netting.  An added benefit is that putting the netting on after sowing appears to have improved germination.

Tee Gee

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Re: Optimum size for raised beds.
« Reply #4 on: October 19, 2021, 12:23:05 »
This is my view on the subject

  http://www.thegardenersalmanac.co.uk/Content/R/Raised%20beds/Raised%20Beds.htm

Click on pics to enlarge!
« Last Edit: October 19, 2021, 12:25:39 by Tee Gee »

Deb P

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Re: Optimum size for raised beds.
« Reply #5 on: October 19, 2021, 14:55:19 »
If you have cloches, make the beds wide enough to fit them neatly. Mine are all 8’x4’ because we used free lumberyard pallet wood to make ours and that was the size it came in!
If it's not pouring with rain, I'm either in the garden or at the lottie! Probably still there in the rain as well TBH....🥴

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Tulipa

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Re: Optimum size for raised beds.
« Reply #6 on: October 19, 2021, 15:29:15 »
Mine are 8' x 4' I am only 5' tall so any wider would be difficult to reach the middle. As for length it is worth thinking about not too long as when you are working you need to move to the other side and longer beds become difficult to walk round, walking over them defeats the object as you compact the soil but becomes very tempting.  8' gravel boards work well to make 8' x 4' too.  Also most netting or fleece tunnels fit well on a 8' bed.

Tee Gee

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Re: Optimum size for raised beds.
« Reply #7 on: October 19, 2021, 17:04:11 »
To cater for your particular height kneel at the edge of the bed lean forward as if you were weeding/planting out.

Once you find a position you are comfortable with, measure from the edge of the bed to the weed/plant and double it.

Example; stretch point = 60 cm (2ft) x 2 = 120 cm (4ft) this is the width of the bed you require.

Another thing you can do at the same time is to determine the width of footpath/s.

Again, kneel at the edge of the bed and mark where the toes of your footwear is and mark this point as this will be the minimum** width of your path.

**Alternatively; if you use a barrow (or a wheelchair in the case of the disabled) make your footpath to suit the appliance!

ps should you share a plot with someone who is much taller/shorter than you, you will have to arbitrate although common sense says measure for the shorter person of the two would be best in most cases!

George the Pigman

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Re: Optimum size for raised beds.
« Reply #8 on: October 20, 2021, 12:21:40 »
Thanks for your ideas.  4 foot wide seems to be the consensus and that fits with what I see on our allotment. Length seems to be optional.
What about height? TeGee recommends 24 inches but on our allotment I would say they are no more than about a foot above ground.

Tee Gee

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Re: Optimum size for raised beds.
« Reply #9 on: October 20, 2021, 13:06:43 »
Quote
height? TeGee recommends 24 inches but on our allotment I would say they are no more than about a foot above ground.

I think this is a grey area for example I don’t consider anything up to 6” high a raised bed.

I see such beds as a means of improving the depth of shallow soil or improving the existing soil particularly those types of soil that lack natural humus.

I see heights of  6” to 24” as variations of the above rather than for disability.

The 24” is to cater for wheel chair users or people who can not kneel down.

Then of course it might just be to form a feature in the garden and may be constructed with masonry,

Plot22

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Re: Optimum size for raised beds.
« Reply #10 on: October 20, 2021, 15:38:46 »
My wife has raised beds at home 2 in the middle of our 750square metre lawn and one covering almost the entire 25 odd metres of the bottom of our garden approx 20 metres by 6 metres. She makes them look really fantastic but initially the main problem was how do you fill them?. We planned it like a military operation and without the allotment we would not have succeeded. We transported bag after bag of rotted leaves which we had taken down to the allotment to decompose in the bins plus bag after bag of farmyard manure. Result we filled them all but still after top them up every year. The most important aspect of raised beds is filling them. My neighbour at the allotment site has converted 20% onto raised beds. 50% onto a chicken run and 30% onto a normal allotment plus his paths. I could not feed my family on that amount of growing space so I will stick with my conventional allotment  but each to it's own.
« Last Edit: October 20, 2021, 15:44:29 by Plot22 »

Paulh

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Re: Optimum size for raised beds.
« Reply #11 on: October 20, 2021, 18:22:16 »
"How do you fill them?" is linked with what you do about paths.

You don't want to waste the top soil which will be where your paths will be permanently, so you should consider stripping it off and setting your beds lower (and perhaps using deeper boards to compensate).

You don't want to have to spend time clearing your paths of weeds, so make sure you can mow or strim them, or put down weed fabric and cover it with gravel or mulch.

cudsey

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Re: Optimum size for raised beds.
« Reply #12 on: October 20, 2021, 19:03:40 »
I have quite a few raised beds on my allotment and I try to make them about 24ins high so that gives carrots and parsnips some depth but it depends on what you are wanting to grow in them 
Barnsley S Yorks

Deb P

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Re: Optimum size for raised beds.
« Reply #13 on: October 23, 2021, 06:43:45 »
Having spent many hours weeding various sorts of paths (compacted soil, wood chips, both of which just get messy and weedy, membrane and wood chips on top gets blown away and birds love it, I have ended up with paving stones, 2ft wide with membrane underneath. That way you don’t spend more time weeding the paths then the beds! My beds are just edged with split scaffolding boards atm so only about 6” high, but they have rotted much more quickly than my old pallet ones did and with the paving I’m thinking of not bothering to replace them as they crumble….they get topped up every year depending on what’s growing in each bed and I think that and the reduced soil disturbance are the main benefits of the raised beds rather than the edgings which slugs and snails like to try and hide under!


If it's not pouring with rain, I'm either in the garden or at the lottie! Probably still there in the rain as well TBH....🥴

http://www.littleoverlaneallotments.org.uk

Vinlander

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Re: Optimum size for raised beds.
« Reply #14 on: October 29, 2021, 20:12:11 »
Having spent many hours weeding various sorts of paths (compacted soil, wood chips, both of which just get messy and weedy, membrane and wood chips on top gets blown away and birds love it, I have ended up with paving stones, 2ft wide with membrane underneath. That way you don’t spend more time weeding the paths then the beds! My beds are just edged with split scaffolding boards atm so only about 6” high, but they have rotted much more quickly than my old pallet ones did and with the paving I’m thinking of not bothering to replace them as they crumble

Two problems it seems. 1) wood chip won't stay put unless it is deep enough to interlock - if you have enough supplies you can dig out the spit of topsoil you're currently walking on (even if there is stone on top) and replace that spit with woodchip. It will stay there rotting into chocolate brown soil improver, but you will need to top it up as it rots - probably  every 6 months to keep the level right.

One option for the right level is right up to the raised soil level - and if you do that you can remove the planks and store them dry (solving problem 2).  2 or 3 years later when you harvest your soil improver you'll need them to support the trench until you can fill it with fresh chip. You only ever need enough planks for the one trench you're working on.

If the chip supply isn't good enough (because everyone else is letting it blow away), then you can use prunings (cut to 20cm-ish - mainly to make each piece straight enough to pack down well). Prunings are actually much better on wet ground (especially wet paths you use every day), because really wet chip can become wooden quicksand! Though prunings do take an extra year to become soil improver.

Cheers.
With a microholding you always get too much or bugger-all. (I'm fed up calling it an allotment garden - it just encourages the tidy-police).

The simple/complex split is more & more important: Simple fertilisers Poor, complex ones Good. Simple (old) poisons predictable, others (new) the opposite.