[madcat]

Last year we put spuds in the worst bit on our plot for couch grass and horse radish ( ) and it did make a real difference in setting it all back.  This year, there are still roots but we are talking about a bucket of weeds from 6 rows, rather than the two buckets a row when we cleared it before the spuds.   

Might have been better than that if our neighbour hadn't put his plot down to black plastic and then ignored it for the rest of the year.  The grass just went sideways to find the light.     Hey ho, the new peeps that have taken it over seem to be a bit more clued up.

[zazen999]

Thing is, you'll always have some weeds. At least this way you know what you've got and how to get rid.

We have smothered all our beds at various points since getting the plot and planted through mulches like cardboard, weed fabric etc - and getting the roots out hasn't been that difficult when you harvest the crops. The problem with onions is the shallow roots and them not liking competition.

I'd be inclined to give the onion bed a really good sweep in the top 4-6 inches and remove everything that you can and just plant out and as you say, use the fabric for other crops. Then another sweep after harvest and put cardboard/thick newspaper over the top for the winter.

[beanqueen]

My plot is covered with marestail. Last year I laid newspaper between the rows of onions and had great results..doesnt take too long once you get in the swing of it and the papers were covered with some soil. Still need to wed a bit around the set until its a fair size ( after that I leave it as per bob flowerdews's advice)

I then dibbed holes in the newspapers for leeks..again good results until leek moth struck. The paper was just dug in then

I try and keep bare plots covered with plastic until they need planting and then use as  much cardboard/paper/fabric as I can
Works for me

[plum crumble]

sounds a good idea beanqueen - what was Bob Flowerdew's advice by the way?

[beanqueen]

He said to let the weeks grow around the onion once it's developed as it protects it