Author Topic: Creeping thistles  (Read 530 times)

Digeroo

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Creeping thistles
« on: July 29, 2020, 14:06:57 »
Not sure they are a disease, but they are certainly a pest.
The next plot to mine has been empty for some years.   So for several years one of the other plot holders has borrowed my strimmer and strimmed it annually before the thistles seeded.  However, at the beginning of last year he had returned to Eastern Europe and I was ill so the thistles flowered and then....
So my plot was filling up with thistles.
I almost gave up, but with the onset of the virus I thought growing veg would be a good idea.   
Lots of new people have taken plots but they all turned down the thistle plot.
So in the end I took it on, and my husband spend the first month of the lockdown digging it over. 
Since then I have pulled up more than 1000 thistles.  But they have underground rhisomes so as soon as you pull them up they pop up with more.  Pull up one, and two appear and then there is a row of them.
I planted the plot with courgettes and pumpkins which I know discourage weeds.  But it seems that creeping thistle are exempt.  (as are nettles, comfrey, fat hen) Though the couch has not put in as much of an appearance as I had feared.   
So the question is how do you get rid of creeping thistles?  They are the ones with small pinkish flowers.
The farmers sprayed some of the thistles near the hedge with some weedkillers but this seems to have stayed in the soil and a few of my squashes and courgettes are not best pleased.  I managed to move several, and once the soil is washed off they are doing well and producing normal non pointed leaves.   
In general the plots is growing things superbly.  Several people have been annoyed they did not choose the plot.   In order to be quick, I dumped piles of manure and then planted four pumpkins, squashes or courgettes round each pile.  Hopefully they keep the moisture in the soil, so less water is needed.  With the recent rain the plants have now taken off big time, but so have the thistles. 
I also have dwarf beans and thistles, carrots and thistles, a flower border with assorted thistles, tomatoes, cucumbers and chillis with thistles, and baby corn with thistles.   I pull up 50 a day but that is not enough. 
And horseradish!!  That needs to go too but is in the middle of the raspberries.


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Creeping thistles
« on: July 29, 2020, 14:06:57 »

Tee Gee

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Re: Creeping thistles
« Reply #1 on: July 29, 2020, 14:57:39 »
Quote
Since then I have pulled up more than 1000 thistles.  But they have underground rhizomes so as soon as you pull them up they pop up with more.  Pull up one, and two appear and then there is a row of them

Creeping Thistles are perennial weeds that are best dug out completely to prevent spreading.

You mention Couch well Creeping Thistles are similar i.e. leave a piece of root in place at your peril


Digeroo

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Re: Creeping thistles
« Reply #2 on: July 29, 2020, 15:37:23 »
I have learned to cope with couch.  I dig over and turn it upside down and put it at the bottom of the hole and plant a courgette on top.   
But creeping thistles are in a different league altogether.  The concept of digging every last piece out may be an impossibility.  My plot neighbour left a patch covered for two years and as soon as she took off the cover there it was popping up.  So the rhisomes can stay viable under the soil for years just waiting for their moment.
Hope to dig it through before the winter and remove as much thistle as possible but I just cannot believe we well get rid of more than 80-90%.  There will be a lot of peril!!
The only hope will be that when they do pop up, they will be attached to a piece of rhisome and so more can be pulled out in the spring, whereas at the moment you pull and it just breaks off at the rhisome, there is no pointed root most of the time.   
I have about five years worth of accumulated rhizome.  Another solution might be pigs, but they do not eat thistle.  Though they will eat nettles and couch.   Possible thistle is one of the few things they do not eat. 




Obelixx

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Re: Creeping thistles
« Reply #3 on: July 29, 2020, 15:48:09 »
Cardboard?   Just put some down between plants you want and hold in place with pegs or piles of manure or compost?   The rhizomes might stay but it wouldn't be thriving and flowering and seeding and would be weaker when you need to dig some up for a new season's planting.   No plastic waste to dispose of and the cardboard adds to the sil and its micro organisms.   
Obxx - Vendée France

JanG

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Re: Creeping thistles
« Reply #4 on: July 30, 2020, 05:16:22 »
My theory - and hope - is that if they’re pulled up often enough they eventually give up the ghost. I have a veg bed where there were thistles and after a couple of years of pulling up, they’ve faded out. They don’t persist in regularly cut lawns and I guess it’s the same principle.

I sympathise though. In the last year I‘ve borrowed a bit of meadow from a neighbour and created beds in one corner. There are three main perennial weeds - hogweed, the least problematic, amphibious bistort, which might well be impossible to get rid of, and creeping thistle, by far the most painful of the three!

ancellsfarmer

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Re: Creeping thistles
« Reply #5 on: July 30, 2020, 08:30:11 »
Knock them off with a dutch hoe when 9" tall, before they knot to bloom.They will shoot again but deep root so are drawing minerals up from the subsoil. They produce a good amount of biomass and compost readily without coming through.I get few weeds with no dig but try to harvest for composting as much biomass as can be garnered from all sources. Dead nettle is another worthy contributor.
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