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Author Topic: onions under plastic?  (Read 2983 times)

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onions under plastic?
« on: October 28, 2010, 12:51 »
hi all, Has anyoe plantented their onion bulbs under plastic and  if so how did it work out? the idea is to save time and effort hoe'in weeds inbetween. Idea is to lay down plastic nd slit hole and pop bulb in. Thanks.


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Re: onions under plastic?
« Reply #1 on: October 28, 2010, 20:03 »
Someone with better knowledge and experience will be along shortly no doubt but I can forsee a couple of potential issues with using plastic as oppose to weed membrane. All manner of beasties will set up home under the plastic safe from predatory birds etc, also given plastic is impermeable it could get a little dry under there and making watering/feeding the onions a bit awkward.
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Jay The Digger

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Re: onions under plastic?
« Reply #2 on: October 28, 2010, 20:19 »
An interesting idea, as onions hate competition.

However I can think of a couple of immediate drawbacks, watering being the main one.  To bulb up to a nice size, onions need a surprising amount of water and getting it to them through plastic would be a headache.  Using weed supprecent fabric would be better but would still suffer from problem 2 below.

The other problem comes when they start to rise out of the soil towards the end of the season.  If the hole is too small it will lift the plastic and be trapped underneath so it cannot dry out.  If it's too large then you will be weeding anyway.  Likewise when they sprout, if the hole is too small and they miss, you will lose the plant.

As onions swell throughout the season, you will never be able to cut the plastic to the right size all the time, which means you will still end up weeding, and take time recutting holes.

It's probably quicker to hoe.    :D


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Re: onions under plastic?
« Reply #3 on: October 29, 2010, 10:19 »
The old guys on my site swear by growing onions thru weed fabric. It is a bit of a faff to cut all the holes at first, but saves a lot of time later weeding. You will need to weed what manages to find the hole but once the onion starts to grow it blocks much of it. I used this to grow garlic last year and have just planted my garlic and winter onions for this year thru weed fabric. You do need to cut crosses big enough to allow the onions to swell above the hole. I found I damaged a fair number of my own onions with my hoe last year. I did plant them fairly close so it was a close fit to pass the hoe between the onions and I uprooted a few and cut some as well. It is best to use the wider fabric, get the ground raked level and them let it settle a bit before planting thru the holes. You could give it a go and compare which is least trouble. The fabric can be used for a few years with care.


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Re: onions under plastic?
« Reply #4 on: October 29, 2010, 15:14 »
I agree with others' reservations about plastic.  As well as preventing moisture getting to the onions, at the other end of the extreme it may trap excess water, leading to ideal conditions for fungal spores to thrive under the warmed plastic.
I try to take one day at a time, but sometimes several days all attack me at once...


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Re: onions under plastic?
« Reply #5 on: October 29, 2010, 15:19 »
weed control fabric is what to use.

All the old boys with double plots use it to cut down on the weeding.
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Re: onions under plastic?
« Reply #6 on: October 29, 2010, 18:28 »
thank you all for your answers. I am going to try the fabric this year and see how it goes. Yes I damaged onions with the hoe last year also.

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