Growing onions through black and white polythene

[rary]

A while ago I heard a talk on growing onions and the speaker said that he covered the soil using a black and white poly sheet early spring he covered the soil with the poly black side up, this was to heat up the soil, then when ready to plant his seedlings he turned the poly sheet to white side up cut X`s in it and planted through the poly sheet, he said that he never needed to water the onions nor did he have weeds, but he did have crackers of onions unfortunately I don't know what variety of onion he was using, but intend trying this method this year, has anyone ever grown their onions this way?

[Teds Mum]

I've not tried this, can see how it might work though. Onions don't do well with competition from weeds so the plastic would help there. However it would be an unwieldy method on a larger scale, I grow hundreds of onions, they occupy about a third of my plot at the moment. Also I worry about providing hiding places for slugs. For a few dozen giant onions for show it sounds an excellent method, worth a try.

[Thelma Sanders]

Exhibition growers use it, but you would need to water around individual plants or use an irrigation system underneath, as no rain can get through the sheet material.

[veggiechicken]

Sounds like a lot of potch and a great haven for slugs - and you end up with a sheet of holey plastic to dispose of.

[Snadger]

My allotment neighbour has used the same sheet of holed plastic for years to grow his onions. Its black and has three inch diameter holes cut into it at regular spacing. He alternates the area he grows onions each year. His onions always appear to be on the small side to me but perhaps that's the way he likes them. He never seems to feed or add organic matter to the area he grows in so that could be why.

[Aberdeenplotter]

has anyone ever grown their onions this way?

That's what I do in my polytunnel with my show onions, big ones and small ones.

[rary]

Sounds like a lot of potch and a great haven for slugs - and you end up with a sheet of holey plastic to dispose of.

On reading your post today VC I went out to check what was under the cardboard that I have covering my beds and underneath the cardboard there were several slugs, so on seeing that I will scatter some organic slug pellets when I turn the poly to the white side up

[rary]

Exhibition growers use it, but you would need to water around individual plants or use an irrigation system underneath, as no rain can get through the sheet material.

The gentleman that gave the talk did exhibit onions, and he was asked about watering and he said that he never needed to water the plants, which in this area of Scotland is understandable as generally the only things that need watered are baskets and tubs

[Snadger]

On reading your post today VC I went out to check what was under the cardboard that I have covering my beds and underneath the cardboard there were several slugs, so on seeing that I will scatter some organic slug pellets when I turn the poly to the white side up

I suppose you have to remember that slugs play an important role, along with other invertebrates in breaking down the likes of cardboard and other organic matter.

[rary]

I suppose you have to remember that slugs play an important role, along with other invertebrates in breaking down the likes of cardboard and other organic matter.

Yes you are right Snadger,but there's a big empty field over the boundary hedge so they are welcome to go over there and break down the organic matter there