I'm about to make some raised beds on a patch of ground that has a problem with columbine. Should I use some landscape frabric under them to help with weed supression to?
It's probably a bit late in the year to treat sucessfully with glyphosate weedkiller. I'd dig it over a couple of times before even contemplating beds on an area infested with bindweed. That way you can try & remove as much as possible of the roots.
Then I'd cover the area with the weed membrane & leave it over the winter until spring next year. When you remove the membrane you'll soon see if/when the bindweed returns & can retreat asap & repeatedly until it, hopefully, gives up. Then go ahead with the beds. No easy way to ensure it's prevented from growing again.
Yes the membrane will stop weeds coming from beneath, but also prevent roots going deep for your plants. Also any tear of the membrane will allow the bindweed access to your bed again, so trying to eradicate it before you do the beds will pay dividends in the long run. Sorry to be so negative, but bindweed is very determined. J.
Jeff didn't say bindweed, he said columbine. I think landscape fabric sounds a good idea.
Yes I just assumed, possibly incorrectly? that the OP meant bindweed. I'm hoping that my repeated attacks on it at the front have worked, but if not,it actually looks quite good flowering over a boring Laurel bush.
Aquilegia is easily pulled out where not wanted, although I do leave some 'choice' specimens alone.
Agree the thick cardboard layer would be good & probably quite a bit cheaper too! J.
Yes You're all right, it's bindweed I've got. I like the cardborad idea as I manage a cycle shop so no supply problems. Thanks to everyone for the help.
Here's an article by her on the subject, but she goes into more detail in her book 'The Thrifty Gardener'. Googling 'pizza gardening' will also give more info.
I lined my 3 raised beds with thick cardboard, then sifted top soil, compost, Chicken poo, anything I could get. The cardboard has been a great suppressant. I am hoping to get an extra bed and have already got my extra large, thick cardboard box ready.
Thanks bjay, I'm going with you and using cardboard with soil and compost on top.
At the suggestion of someone on here (sorry can't remember who) I put a sheet of permeable membrane in the bottom of my new wooden raised bed last year and stapled it to the sides (so it came up the inside sides about 4"). The theory was that this would stop the soil washing out of the bottom of the bed when I watered/when it rained. It made sense to me so I did it.
I also lined the inner 'walls' with thick polythene (from the garden centre) also stapling it to the sides, to prevent leaching of any wood preservative - this was recommended by the manufacturer.
So far so good, we've had a good crop of courgettes, now winter lettuce seedlings are growing well - no slug damage (so far). And no expensive topsoil and farmyard manure leaching out of the bottom.