Black Plastic -

[tim]

- recommended for weed supression - does the soil not get bone dry underneath?

[tim]

[OllieC]

Certainly does Tim. And I reckon that using it for more than a few months must be bad for the soil as it would kill off the microorganisms, further reducing the speed with which you'll get the soil back into good condition. My plot's on a slight slop, and I used overlapping strips, arranged for the water to flow under the sheets. Then I just took the whole lot off and went for Roundup a bit later! At least it only kills the plants.

You don't mean the permeable weed suppressant stuff, do you?

[tim]

No - 'cos that would be no problem.

[glosterwomble]

- recommended for weed supression - does the soil not get bone dry underneath?

Not really in my opinion. We used it to mark out where we were going to dig the beds when we took over the derelict plot and then, when we have dug the bed over, if nothing is going straight in then we put the plastic back down to stop weeds coming up (obviously we could sow a green manure at this point instead). I think it would be very difficult to make an area sterile or killing off all the microbes etc. by doing this, when we have lifted the plastic we find lots of life underneath, from sloe worms, earth worms and lots of creepy crawlies.

If you were meaning that you wanted to plant THROUGH the black plastic to use it as a sort of mulch then yes I would say buy the proper permeable stuff to let enough water through for the plants.

[caroline7758]

I grew courgettes very successfully through black plastic which had been down for at least two years! When you lift the plastic it does seem dry on top but there's still lots of moisture underneath. Maybe due to condensation?

[OllieC]

Ahhh, now I was a bit tired yesterday & only gave half my story. When I first got my plot, it was covered in a huge, single piece of black plastic, the size of a 10 rod plot. This was very dry from about the middle, down to the bottom of the slope. So I cut this into smaller bits before getting rid altogether.

So, perhaps size matters in this instance?

[tim]

No, Womble - just wondered whether, after a winter of cover, the soil would be in a fit state to plant in, moisturewise.

[glosterwomble]

No, Womble - just wondered whether, after a winter of cover, the soil would be in a fit state to plant in, moisturewise.

I think it would be fine Tim, it certainly seems ok for us and as Olliec said it would only be dry in the middle if you covered the entire garden/plot, if only covering a bed or small plot then water must come in from the edges.

[glosterwomble]

....and another thing, it warms the soil slightly so you can sow slightly earlier, that is something recommended in several books I have read!

[Froglegs]

Would it not depend on the ground being wet or dry before you put your plastic down. :-\

[Deb P]

I used black plastic successfully at the beginning of this year to cover some beds after manuring heavily to avoid the nutrients being washed out by rain, suppress weeds and to let the worms do the work for me overwinter. The beds were all newly made and dug over to start, I then manured and covered the back 4 beds and left others uncovered....



Results were excellent, the manure had been reduced by about two thirds by late March, the top was slightly dry but underneath was moist and full of worms! These beds kept their moisture really well throughout the dry April too. The uncovered ones were very wet, had more weeds and perversely dried out a lot faster in the dry spells, in some places the soil cracked but the crops were fine. I shall be using the same method again this year on the next four beds!

[tim]

An example to all?

[glosterwomble]

Would it not depend on the ground being wet or dry before you put your plastic down. :-\

To be honest I don't think it would matter, the rain will seep along underground anyway, obviously the wetter the ground is when you cover it then the damper the soil will be when the plastic is lifted but you are only covering the top of the soil not sealing it from underneath so moisture will penetrate.

And Deb P your plot really is beautiful!!  ;D

[saddad]

She's an inspiration to us all GlosterWomble...  ;D

[OllieC]

And Deb P your plot really is beautiful!!  ;D

Can't argue there! I wish mine looked that good!

[caroline7758]

One thing I would say to anyone thinking of using black plastic (sorry, off thread slightly here) is DON'T dig it in round the edges. It may be more effective in blocking out light, but trying to dig it out later is a real b****r!

[Deb P]

Shucks I'm blushing.... :-[

I've never tried digging the edges in Caroline, just chucked the inevitable abandoned plot bricks on top to keep the plastic  from flying away in the gales....
It is a lot easier to do on raised beds of course.. ;D

[antipodes]

Hmm I grow my strawbs on black plastic and I dug in the edges. I find that it is quite moist underneath, but the sections are not very big so guess that moisture seeps in round the edges. It is not foolproof, I still get bindweed growing up the strawberry plants, sneaky bardfast, but it is better than nothing at all. I have used it on the new strawberry bed, too.

[caroline7758]

To be fair, it was the previous tenant who had dug in the edges- maybe if you've done it yourself and know how deep it is, it might be easier!We now just use bricks, too.

[RosieMcPosie]

deb, that's lovely! well done u!
i'm hoping mine will turn out something like that soon! i'll post pics when i get home  ;D