Canada Thistle

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brownrexx
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Canada Thistle

#1

Post: # 45150Unread post brownrexx
Sun Apr 18, 2021 8:03 am

Canada Thistle! Aghhh.

I have had a small patch of this in my garden for several years. I always gently pull out the plants but the root breaks off and of course they always grow back.

This year I can see the I have more than usual and I knew that I had to do something. I was going to try vinegar but I Googled and most people say that it only kills the leaves. Why bother with that?

Google also says not to dig because of leaving parts of root in the soil which will regrow but I had to do something and 2,4 D is not an option since I garden organically so I got the shovel and dug really deep.

The soil was wet as deep as I could dig so it was easy and then I used my gloved hands to tease the soil apart and remove the thistle plants and roots.

I was able to remove about 50 small plants and I felt like I removed lots of the main roots but I am sure that I didn't get them all.

Does anyone have a better way of dealing with Canada Thistle?

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Nan6b
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Re: Canada Thistle

#2

Post: # 45167Unread post Nan6b
Sun Apr 18, 2021 11:11 am

I was going to suggest digging deep. Now that you have done it, examine the plot from time to time. If you see some coming back, do the same thing again. You surely got the whole root on some of them. So if you persist, you'll surely get the root on more of them. I have a shovel that is very long and narrow that is perfect for that kind of root removal.

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Julianna
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Re: Canada Thistle

#3

Post: # 45168Unread post Julianna
Sun Apr 18, 2021 11:15 am

If you keep killing the leaves it will eventually die. It is a long process, but it cannot live on stores forever.
-julianna
10a Monterey Bay
Lover of Fogust, tomatoes, flowers, and pumpkins

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bower
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Re: Canada Thistle

#4

Post: # 45233Unread post bower
Mon Apr 19, 2021 10:03 am

Yes, you did the right thing by digging deep in spring while the soil is soft.
You could cover the spot with cardboard at this point and see if that suppresses any survivors.

As Julianna said, the other recommendation for really difficult weeds is to cut the tops mercilessly all season long. Then when you go to dig the roots they are already much weakened. Combinations of top cutting, root digging, and suppressing by covering the soil with a barrier, seem to be most effective with the most awful things. Bamboo is one, goutweed another - I never heard of Canada Thistle being real trouble but if the area is perennial I could see it. We have some here around the gravelly road edges etc and I have pulled some out of the beds at my Mom's garden, but was not a big deal as they were coming from seeds and not from a long established root system.
AgCan Zone 5a/USDA zone 4
temperate marine climate
yearly precip 61 inches/1550 mm

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brownrexx
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Re: Canada Thistle

#5

Post: # 45242Unread post brownrexx
Mon Apr 19, 2021 12:34 pm

Bower wrote: Mon Apr 19, 2021 10:03 am I never heard of Canada Thistle being real trouble but if the area is perennial I could see it.
They are very tough to kill and grow by rhizomes with little plants popping up all along the rhizome's path. I never let them flower or go to seed so at least they are contained in just one area and have not spread all over the place.

They are also full of thorns and fight back when I try to pull them! Grrr, they are nasty things!

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Growing Coastal
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Re: Canada Thistle

#6

Post: # 45279Unread post Growing Coastal
Mon Apr 19, 2021 9:26 pm

Canada thistles are among the worst weeds to get rid of. I had so many of them in one garden that I used to take a small hand sickle and slice them off at the ground. Impossible to dig them all out.
One year my peas had an infestation of black aphids. Gross to pick the peas, yuck! I left a few thistles alongside the peas and the aphids transferred to the thistles. I'd read this about Canada thistles in a gardening magazine and it really worked.
Pollinators love them and they scent the air nicely in the wild.

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Shule
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Re: Canada Thistle

#7

Post: # 45287Unread post Shule
Tue Apr 20, 2021 12:41 am

I've read that Canada thistle is edible; supposedly, you can curdle milk with the flower heads, too. I'm not sure what Canada thistle tastes like, but Mary thistle leaves taste just like lettuce.
Location: SW Idaho, USA
Climate: BSk
USDA hardiness zone: 6
Elevation: 2,260 feet

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brownrexx
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Re: Canada Thistle

#8

Post: # 45294Unread post brownrexx
Tue Apr 20, 2021 6:49 am

I think that I will just stick with real lettuce [mention]Shule[/mention] I want these miserable thistles gone!

Chickweed is another weed that I struggle with and I heard that it was edible so I tried cooking a batch. Yuk. I was not impressed.

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bower
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Re: Canada Thistle

#9

Post: # 45296Unread post bower
Tue Apr 20, 2021 8:06 am

I like chickweed but never cooked it. A nice handful on a sandwich is a great substitute for lettuce. Cut before flowering. ;)
AgCan Zone 5a/USDA zone 4
temperate marine climate
yearly precip 61 inches/1550 mm

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Julianna
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Re: Canada Thistle

#10

Post: # 45302Unread post Julianna
Tue Apr 20, 2021 9:42 am

brownrexx wrote: Tue Apr 20, 2021 6:49 am I think that I will just stick with real lettuce @Shule I want these miserable thistles gone!

Chickweed is another weed that I struggle with and I heard that it was edible so I tried cooking a batch. Yuk. I was not impressed.
I haven't cooked chickweed but eating it raw is nice. It is mild, like lettuce.
-julianna
10a Monterey Bay
Lover of Fogust, tomatoes, flowers, and pumpkins

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