Raised beds or No Raised Beds

[alldigging]

Timber Supplies do wood for allotment beds.

They have stuff with a really long guarantee on it too!

[MarkHackwell]

Now I have been down the allotment I have decided I am going to lift the raised beds and put down black polythene before putting the Raised Beds back. The question is would it be better to leave them as they are at the moment or make 2 long ones, one either side of the Greenhouse would you think?

[Kristen]

Now I have been down the allotment I have decided I am going to lift the raised beds and put down black polythene before putting the Raised Beds back

Under the beds, or just to separate the timber sides from the soil?

I wouldn't want the soil in the beds separated from the ground beneath - benefits of greater cultivation depth and reserves of water for the plants growing in the beds.

[veggiechicken]

I'm confused about what you're trying to achieve? You're talking about lifting the beds, removing a foot of soil, so that you can put down plastic sheets, then putting the beds back and refilling with the soil. Sounds like one heck of a lot of work to overcome some weeds, that regular hoeing and weeding could resolve. You'd probably end up with a bog garden anyway, unless you put in drainage.
If you can't cope with the weeding, cover the top of the beds with the plastic and get on with the rest of your plot.

[MarkHackwell]

Under the beds, or just to separate the timber sides from the soil?

I wouldn't want the soil in the beds separated from the ground beneath - benefits of greater cultivation depth and reserves of water for the plants growing in the beds.

I was going to put it under the raised beds in order to separate the soil from the raised beds as I have a problem with Couch Grass

[MarkHackwell]

I'm confused about what you're trying to achieve? You're talking about lifting the beds, removing a foot of soil, so that you can put down plastic sheets, then putting the beds back and refilling with the soil. Sounds like one heck of a lot of work to overcome some weeds, that regular hoeing and weeding could resolve. You'd probably end up with a bog garden anyway, unless you put in drainage.
If you can't cope with the weeding, cover the top of the beds with the plastic and get on with the rest of your plot.

What I want is either 2 long raised beds or 2 slightly long and 2 square, unsure yet. and that was what I was planning but like you say it will be a lot of work. The problem I have having at the moment is that the paths round the raised beds were all weedlinered and mulched with bark but the couch grass has taken them over and has grown from the bottom of the raised beds and through, so unsure how to tackle it without taking out all the compost and weed lining the bottom of the beds, as the paths need re-doing anyways. but as you say by using black polythene it may well cause a bog garden. Would I be better covering them up for now then or be better getting the compost out and digging the bottom then putting the compost back in, weed lining the paths and be done like that?

[Kristen]

I was going to put it under the raised beds in order to separate the soil from the raised beds as I have a problem with Couch Grass

I think its a bad idea - having the beds open to the world below and, preferably for my money, dug properly before the raised bed & filling-soil is placed on top, will provide good drainage and the opportunity for roots to run deep and haul up nutrients. Raised beds dry out more quickly than flat beds, so roots running deep (for those crops capable of that) will be less troubled by drought.

Another example: for Beans it is advisable to make a trench, chuck in all sorts of organic matter (even if not well rotted), to help retain moisture. With a plastic base there won't be enough depth available. Also, sooner or later it will be punctured by some cultivations.

If weeds are a problem which cannot be solved by weeding (e.g. not enough time available) then I recommend mulching instead. Even if Couch does not invade all sorts of other weed seeds will arrive on the plot and grow ... and need weeding. Mulching will solve that problem too.

My personal approach is to use Mypex woven plastic weed suppressing membrane. Woven is important, there are other brand available, pick one that is UV stabilised. If you were happy to put plastic under the beds then I am guessing you will have a budget that could afford Mypex, but if not look at Cardboard instead. That's a one-season product though, so would need renewing each year.

Here are my Leeks, recently planted in July:


and again in October:

[MarkHackwell]

Keeping of Raised Beds but a change round not too sure about. Opinions and Ideas?

Well I have decided to keep the raised beds and not weedliner the bottom of them but I have moved one of them around to see what it would look like with two longs ones either side rather than 4 raised beds. Here are the before and after photos: Could you give me opinions on them and ideas of what I could do if you think it's not the best way of doing it

Before:



After: