Wednesday, 31 October 2018

Weed Suppressant Fabric - Cure or Curse

This picture, for me,  encapsulates the case for Weed Suppressant Fabric.  The net overhead and the collars around the plants give away that this was my brassica patch (in 2017).  The strip to the left: no WSF.  The rest to the right WSF applied in early spring. Which would you rather be faced with come the month of June?   No contest.  This trial evolved as a result of my wish to leave a strip in which to sow later brassicas that will not tolerate transplanting (Swedes, Pak Choi, Mooli) and was not staged to prove a point. None the less as I crouched on hands and knees under the net I thought it was worth taking this picture for the record, ready for that Autumn day when I would be warm indoors mulling over the lessons learned.  16 months later that day has arrived. 

I do still have reservations.  The fabric is made of woven plastic and is not biodegradable (although it lasts for years and is reused).  It allows water through the weave but there are concerns for the effect it has on the soil/air interface.  Do insects and worms like or abhor it and how does that affect the soil food web? I see the Garden Organic guidelines approve of it only on a limited basis for clearing weed patches although it is acknowledged as a longstanding tool for growing organic strawberries.  A web search has plenty of rants against "landscaping fabric" in vegetable patches which surprises me some as I have not experienced the problems they describe.  (Usually someone is renovating a recently acquired garden where the previous occupant has laid down a layer below soil level and weeds have grown on top. ) My piece follows (or rather precedes) the brassicas around the plot and has the bonus of already having the holes spaced out at just the right distance for planting. 

For now, I will continue to use it on my brassica patch in order to reap the benefits, but I am now wary of leaving it down in one place for more than one season.  I have just recently decided to carry out a worm survey of comparable patches with and without WSF to see if there is any discernible drop in numbers.  If you can save me the trouble by pointing to any research on this topic - do please let me know.  I don't know about you but I just find weeding a chore.


  1. We just couldn’t manage our allotment without it and certainly find crops grow better now we use it.

  2. Having used wcf for a number of years now I haven’t noticed any long term issues. There again I haven’t looked on the Internet to see what the problems are supposed to be. Knowing the Internet I’m sure that somebody will have found some.

    Most of our beds are covered for a couple of years before getting a year uncovered. The covered beds aren’t necessarily covered all year either they may be left uncovered for a few weeks up to a few months.

    Not noticed any increases in pests and a couple of beds left uncovered over summer certainly didn’t benefit from been leftists uncovered.

  3. As they say "The results speak for themselves". I have been reading recently about the soil food web and wondered whether WSF enhances or detracts from the efficiency of its operation. I think there is a chance that it enhances it because the fabric is breathable and water permeable. On the other hand the organic matter in the soil, once broken down fully, cannot be replaced without lifting the cover. Maybe after a few years unattended there could be a danger of the soil becoming sterile. The key visible indicator is worms, so that is what I will use to explore this issue. The other visible indicator is the health of the crop. So far alliums, brassicas, cucurbits, soft fruit... all seem to be fans.

  4. I have used it in the past, last year after a slow start and rush to plant I forgot. I found it good but bind weed used to grow under it and pop up through the holes. It was very difficult to weed out.

    Cover the plot every winter though