Author Topic: Raised bed width  (Read 835 times)

elhuerto

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Raised bed width
« on: November 04, 2017, 10:58:48 »
Long time, no post :-)

I've been given some wood, 88 metres of pine flooring that's probably a tad warped so thought I'd make some raised beds this winter. They come in 2 metre lengths and about 25cm width so I thought of making raised beds of 2metres x I metre and doubling up for 50cm height. If I have 1 metre width do you think that's enough for say two rows of smaller stuff like peppers, chilis, aubergines, peas, dwarf beans etc but one row of larger plants like cokes, courgettes etc.?

The wood is untreated it seems so what would you recommend for that?

Cheers
Location: North East Spain - freezing cold winters, boiling hot summers with a bit of fog in between.

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Raised bed width
« on: November 04, 2017, 10:58:48 »

Tee Gee

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Re: Raised bed width
« Reply #1 on: November 04, 2017, 12:30:13 »
This is my slant on the subject perhaps you can modify this info to suit your situation!

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

Vinlander

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Re: Raised bed width
« Reply #2 on: November 04, 2017, 12:46:48 »
88 metres is a lot of preservative brushwork.

I would recommend that you dig a soaker - a narrow level trench* and line it with a single sheet of sound plastic - then you can paint each plank in there as roughly as you like (much quicker) and at some point the 'waste' will start to soak the back for you so that's the work almost halved.  If the wood isn't too porous you might as well spill a bit extra to keep this going - but that's assuming you got the bottom very nearly level **  The same goes for spraying.

You will need rubber gloves inside your work gloves, and you might need to dump both afterwards - but the same goes for every method.

If your trench is dead level and your wood isn't outrageously porous then it's possible to use an even easier method - just pour the preservative in and dip the planks one at a time (if they aren't very porous you can immerse more at a time) - but make sure you put extra plastic one side of the trench so you can stack the soaked wood and the drips will go back in the trench. It's also possible to cantilever the 'done' planks over the trench but they still get in the way.

About 10% of the work but you will use more liquid - though it will all end up in the wood so that's an advantage... Definitely buy 10% extra - you can get more later - it might need 20% or even 30% depending on the wood. Time is money and money saves time (and effort).

* If you have a convenient level area you can use bricks or timbers to raise the edges of plastic to the same effect - but you still need a draining space - preferably raised so it drains naturally back to the soaker.

** you can make sure the trench is spot-on level by trying water in the plastic before you start (making it into a giant spirit level - this is a modern version of how the ancient Egyptians got their pyramid foundations dead level). A few shallow ripples aren't important but you don't want all the liquid at one end. Obviously get the plastic out for a good shake dry before you add preservative.

Oh, and do the longest planks first so the later ones can be used to mop up the leftovers.

Cheers.

PS. You need the stakes to last longer than the planks - it saves a lot of effort when the planks finally go. A metal pipe driven in more than 50cm will outlast two generations of planks - even a mild steel mop handle will. Properly galvanised steel will outlast 3+ and old cast iron heating pipes will outlast 10+ generations of planks. You don't want the sharp ends sticking up so put old 300-500ml PET bottles on them - or you put the pipes behind the planks and use galvanised coathanger wire  to attach the planks.
« Last Edit: November 04, 2017, 12:55:06 by Vinlander »
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.

elhuerto

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Re: Raised bed width
« Reply #3 on: November 04, 2017, 13:31:08 »
That is really helpful, thanks a lot!
Location: North East Spain - freezing cold winters, boiling hot summers with a bit of fog in between.

elhuerto

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Re: Raised bed width
« Reply #4 on: November 05, 2017, 08:57:23 »
Just one additional question, for treating the wood I was looking at using linseed oil but is there a better (or more economic) solution? I like the trench idea and hadn't thought of doing something like that, makes perfect sense.

Cheers!
Location: North East Spain - freezing cold winters, boiling hot summers with a bit of fog in between.

ancellsfarmer

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Re: Raised bed width
« Reply #5 on: November 05, 2017, 09:10:28 »
Linseed oil works fine but it waterproofs, not preserves. You will do best with raw oil. If you can locate a horse feed supplier, (Such as Mole Valley farmers), you will discover bulk packs (2.5 litre) of food grade(horse) which are zero rated, thereby saving 20% VAT (You may consider this legitimate!)
Expect to recoat after 3 years or so.
Freelance cultivator qualified within the University of Life.

elhuerto

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Re: Raised bed width
« Reply #6 on: November 05, 2017, 11:28:45 »
Thanks, do you mean raw linseed oil or some other type of oil?
Location: North East Spain - freezing cold winters, boiling hot summers with a bit of fog in between.

Vinlander

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Re: Raised bed width
« Reply #7 on: November 05, 2017, 12:42:09 »
Does waterproofing alone have any benefit? I can see it might help on fencing but raised-bed planks rot fastest next to the damp soil they hold up - and I'd expect an edible oil to be eaten by soil microbes in no time(?). Lining might help (see Tee Gee).

Obviously creosote is a no-no for plants - but even that gets eaten by microbes eventually - the only stuff that lasts is heavy metal- based - but avoid chromium like the plague. Fortunately Arsenic is no longer used.

Modern Copper-based formulas are less problematic because when dispersed by natural processes many organisms use it as an essential trace element (including mammals like us).

Apparently the industry is moving towards colloidal copper - interesting as this is the most traditional (and homemade) form of Bordeaux Mixture for blight - but the powers that be have banned all forms of Bordeaux (one law for the rich...).

I just try to find old joists for my beds (thick enough to last up to 5 years) and replace the worst ones by regular skip-diving. I'm worried what I will do when every single house in the area has got its loft extension.

Cheers.

PS. In the UK Sweet Chestnut is the longest lasting local wood, in the US they have Osage Orange that will outlast galvanised steel.
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.

elhuerto

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Re: Raised bed width
« Reply #8 on: November 05, 2017, 18:05:42 »
Really appreciate all the suggestions and after doing a bit of extra reading I'm going to get a good staple gun and line the insides with plastic. The point about the linseed oil is a good one and just not worth the expense and hours of work involved.

Thanks again.
Location: North East Spain - freezing cold winters, boiling hot summers with a bit of fog in between.

Obelixx

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Re: Raised bed width
« Reply #9 on: November 05, 2017, 19:02:05 »
In our Belgian garden we used railway sleepers to level the veggie garden area and they were lined with black plastic sheeting.  Still going strong 20 years later with no treatment on teh exposed wood but theye were old sleepers from the railway so previously treated.  They developed a lovely colony of lichen and moss on exposed surfaces.    The actual raised beds were just planks treated with Cuprinol and they lasted between 7 and 10 years and then we replaced them with roofing beams from a builders' merchant.

In this new garden, we have made raised beds on flat ground?  Haven't found the timber I wanted yet but what we have bought has been treated with a simple mix of 1litre of cheap rapeseeed oil with the juice of a lemon.  Shake well and apply with a paintbrush.  Linseed oil can be very thick and gloopy and doesn't soak in as well.
Obxx - Vendée France

daveyboi

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Re: Raised bed width
« Reply #10 on: November 05, 2017, 23:38:40 »
When I made a raised bed I painted the inside and bottom 2" of the planks with black bituminous paint and left the outside bare ( treated wood ). This allows the timber to dry out in dry spells which helps prevent rotting. The bed is now 8 years old and no signs of rot at all. 
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John85

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Re: Raised bed width
« Reply #11 on: November 07, 2017, 08:37:58 »
Burning the surface also works well , cost only a little gaz and is quick.No nasty chemicals involved.
You can also dip the planks in a mixture of water and ciment.The wood must be very dry so that it sucks as much liquid as possible.Of course not good for plants that need a acid soil.