Plunge beds

[cohan]

the important lesson is to build the plunge bed as far away as possible from any woody species. mine is over my septic bed---a good use for a mostly unusable space.

kristl, that bed is great, and i definitely should have something like this, on a smaller scale...lol
keeping it away from trees would be a desirable idea for many kinds of beds, unfortunately i have no area that is any significant distance from large, established, native, woody species, even in the middle of my largest sunniest clearings there are plenty of poplar suckers, and no doubt all sorts of roots ..i think i will just always have to be nipping off, pulling out and hacking at suckers and roots...
just today i clipped probably a couple hundred poplar stems--saplings from a 18" tall to 10-12 feet; there are many many more to go, plus many that are too big for clippers, and i will be getting the chainsaw to work on those ones.. (these arent all in the 'yard' and 'garden' areas, some are around the edges where i hope to expand the mowable zone for the express purpose of keeping the forest at bay, and some are within the edges of the bush, where i want to thin natural seedlings, keep some areas of forest more open, regulate which species are present in what numbers etc...)

[Alex]

Can I follow up by asking what kind of sand people use? I was planning to use some coarse builders sand with particle size up to about 5 mm (but there is quite a lot of finer stuff in there too.

Thanks for all replies so far, also.

Alex

[Kristl Walek]

Cohan, Unless you have serious issues about chemicals, cut the suckering woody species close to the ground, leaving exposed ends of 1-2" and treat (paint the stumps).  I easily got rid of huge colonies of unwanted suckering woodies in this way---the stumps were also dead in short order.

[Ezeiza]

Hi:

    Our conditions are different, and for most of you could be regarded as very mild. We have used for many years plunge beds made with brick on their sides walls. These walls were lined in the inside with 1 in. or 2 in. styrofoam sheets. We used 16 cm. clay pots and the plunge material for most species was a mix of very coarse sand and sterilized soil. For plants demanding warmer conditions, we used charcoal as the plunge material, that traps a lot of warmth.

     The method was good but we had a couple of catastrophic virus outbreaks that spread throught the plunge material with waterings. Besides, keeping the pots tidy at the same level was a chore. In any case we used it for some 18 years until we shifted to the current method, that proved a lot better under our slight frost conditions.

   

[Anthony Darby]

Cohan, Unless you have serious issues about chemicals, cut the suckering woody species close to the ground, leaving exposed ends of 1-2" and treat (paint the stumps).  I easily got rid of huge colonies of unwanted suckering woodies in this way---the stumps were also dead in short order.

That worked on a balsam poplar tree that I chopped down and produced a forest of suckers all over the garden. I dosed them in the autumn and it was no more.

[johnw]

Cohan - If you decide to paint the stumps with any chemical that is volatile (i.e. produces vapours) then it is a good idea to immediately cover the stump in plastic and close tightly with an elastic band.

A friend treated a stump with 2-4-D without the plastic, within a week a nearby magnolia had rolled leaves on all branches from ground level to 1 metre higher. That probably was not so good for it but the magnolia did survive, just shows you what these chemicals can do.

Another friend treats Acer rubrum this way but she drills holes first and fills them with a bit of concentrate. That does the trick very well.

johnw

[Giles]

Alex,
re Sand.
A counsel of perfection, would be to use horticultural grade, washed, lime free sand.
This is available in bulk, delivered free of charge, from various horticultural suppliers.
(if you want a 'name' let me know).
In bulk, it is less than 1/2 Garden Centre prices.
Builders sand from your local builders merchant, might be ok for your particular purposes, but it can be a bit of an unknown quantity.
(re lime content, and various salts).
It will, however be alot cheaper.
You will need ALOT.
I needed 1.5 tonnes for a 10' x 12' greenhouse with plunge staging on both sides.

[Alex]

Thank you Giles, I will take your advice and get horticultural sand.

I have also found what seems to be an excellent material to line the staging with, it is a weed suppressant which is water permeable but of course won't allow sand through. We shall see.

Alex

[cohan]

Cohan, Unless you have serious issues about chemicals, cut the suckering woody species close to the ground, leaving exposed ends of 1-2" and treat (paint the stumps).  I easily got rid of huge colonies of unwanted suckering woodies in this way---the stumps were also dead in short order.

tks, kristl--i do have issues with chemicals,lol--but not averse to  evaluating individual cases--since i am not always pure of heart enough to allow unfettered nature to reclaim my home and yard fully...lol
so what sort of chemicals are these?
i'm not sure if it would work in my case, since the suckers are coming from live trees which are all around the 'yard' part of the property in all directions, and scattered  through the  yard as well---native aspens and balsam poplar; i am gradually reducing numbers a bit--pushing the bush line back a bit farther where young growth has been pushing forward, and getting rid of some of the aging poplars in the yard, but i think there will always be trees in suckering range of most if not all parts of the yard...

[David Nicholson]

On greenhouse plunges I noted that Alex was using corrugated iron as a base can anyone suggest a lighter alternative please?

[Giles]

David,
My staging came with galvanised metal sheet.
It's not like 'corrugated iron' in the sense of what was used for air raid shelters and the like, and is very light.
Not much heavier than heavy duty corrugated plastic.

[David Nicholson]

Thanks Giles, is your base rested on brick/block piers please?

[Giles]

Each 'bed' is 1800mm long, 780mm wide, and 175mm deep.
It has aluminium sides, and detachable corrugated metal bottom.
Each 'bed' required 270 kg of sand to fill.
It stands on braced aluminium legs, on a solid concrete base.
I didn't bother lining the bed - and no sand has worked it's way out (yet).

[David Nicholson]

Thanks again Giles, can you tell us the name of the manufacturer?

[Giles]

Hartley.
They make shallow 'normal' staging, and this deeper 'plunge' staging.
I think they will manufacture the staging to a range of sizes.