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Are there any herbicides that will kill clover and other weeds, but not harm cactus?

If I had to guess. I would say emphatically, NO!!
Bill in SC

When you say clover, is it possible your are referring to Oxalis?

I think that is something you have to learn to live with. Just when you think you've got it gone, there's another plant.

Daiv

I thought I’d pick-up this thread again, since I'm pulling my hair out pulling these weeds all the time.



(click on image for larger pic)

I have been pulling these out by hand, using a small, relatively soft wooden stick to get in between the ribs of the cactus (E. grusonii). Even though I am very careful and very patient, I never get them all and sometimes even unintentionally damage a spine or two.

The only other way I can think of is to dig up my cactus, separate out all the weed roots and replant. I would hate to have to do this to my plant; it's doing so well.

Do you guys have a better way?

legolas29

That's the way: dig it up and remove the weed. But than again there are some seeds left. What would be the effect of a little roundup put on with a tiny brush only on the Oxalis? A disaster? or will it work? Harry

You can paint the weeds but don't get any on the cactus!

I get those. I just pick them and feed them to my tortoise.

Yup, must be a common and widespread weed. I 've got one growing amidst one of my chollas. I pull out what I can without becoming a self sacrifice and hope the winter will kill the weed off.

All correct advice. I have found that: 1) unpotting the plant and removing the weed roots is the easiest and quickest way. Or: 2) I also agree that you could paint the weed with a paintbrush (actually just a drop on it) and kill it without damage to the cactus. I opt for plan #1..
Bill in SC

Yep that's Oxalis alright! I've just learned to live with it. If I can pull them with my fingers, I do. Sometimes I get out the needle nosed pliers. Trouble is the roots are so prolific on them that they threaten to pull out the cactus too when I get a good grip on them. Once they go to seed, it's all over. You would have to work really really hard to get rid of it all.

On the other hand, I wonder if it isn't helpful to have some growing with the cactus to suck up any extra moisture in the soil.

That little Oxalis can be a booger of a plant to eradicate, it has a tap root, and it has explosive seed capsules that are very effective in redistributing seed. I'm not sure how effective roundup is on this little plant, I guess it does the trick.
For getting weeds out from between/around cacti, some-one once mentioned the brilliant idea of getting a pair of those plier-like instruments with the longish shaft for removing fishhooks. At least it'd be healthier for the fingers, and maybe even better that a stick!

CP.

Yes! Finally an topic i know a bit about! weed removal hey? You can paint a bit of roundup onto the oxalis and it will die, and the cactus will be fine. To prevent more seeds germinating in the pot, see if you can buy a pre-emergent herbicide like Talstar which prevent seeds from germinating. The plant that is already growing in the pot wont be affected in the slightest (but i wouldnt recommend spilling any of it directly onto the cactus). Talstar is like small grains which smell like mothballs, not a liqud herbicide, and it works great