Which Oxalis? One of the more common of the 800 species of plants in this family is Yellow Woodsorrel, something some people think of as a clover with yellow flowers. That is spread by seed eaten by birds so even if one sprayed some poison to kill what is growing in the garden today the birds would replant more tomorrow and the best way to control that is just to keep pulling them out.

OMG - I have been loosing my war against Oxalis for 8 years now... thought I would come on and see what others have done and I read that maintenance is the only way to keep it under control. sigh, oh well. guess this will have to be yearly maint.

thanks

Albin

I pretend it's groundcover.

Try spraying it with regular-strength white vinegar. It works better with shallow-rooted plants like oxalis better than it does with deep-rooted plants like dandelions.

And try to keep it from going to seed.

Sue

I think the yellow flowers on Oxalis are pretty, but it is taking over parts of my yard too. In areas where I am not trying to grow something else I actually encourage it, makes a good ground cover. It is very easy to pull out where you don't want it, but it will probably come back. The bees love it too. I also encourage Scarlet Pumpernel where I am not trying to grow something else even though its considered a weed.

There are some 800 species of Oxalis, many of which are desrieable garden plants while others are considered "weeds", such as Yellow Wood Sorrel.
Yellow Wood Sorrel is easily planted from seed by birds and the only really effective method of control is mechanical, pulling the plants as soon as you see them.

Here is a link that might be useful: Oxalis

The official name for the type of oxalis that is invading California is Oxalis Pes-Caprae. It has light green leaves that look like clover leaves, and pretty yellow flowers, and spreads by both seeds and bulblets. Here is an article about how to get rid of it. Or else live with it and consider it a free ground cover.
http://tncinvasives.ucdavis.edu/alert/alrtoxal.html

I do not know if what I am doing is working, but I am digging it out of the ground a little at a time every day. My Oxalis has a central wine colored "carrot" type root beneath the surface, sometimes a couple of inches deep. If you can find that, it is the motherlode. Leaves on tendrils grow out on the surface for many inches and these all have spider roots. You have to dig under the whole area, then separate the grass from the Oxalis you are removing. Then push your grass back down. Certainly you need to get the "carrot" if you can, but if you only remove several inches of the tendrils, I believe you did help some. Keep your pulled weeds in a box to throw away in a bag. Hopefully never to see the light of day again! Removing just the leaves, is of course, worthless. I have only seen a few of the seeds which seem to work like "stickers" which can attach to objects or animals and spread the plague. I have also used "Weed Be Gone" which is expensive and, as far as I can tell, has little or no effect on the "carrot" root which is the plant's genesis. If you just want the leaves and some of the tendrils to die, it works fine. VERY short term and no solution. Good luck. Advice to the unwary, NEVER let Oxalis get a hold. It's an incredible amount of work to eradicate. It will literally take over your yard.

oxalis pes caprae doesn't go to seed. it's a noxious invasive from south africa and grows by bulb. as the plant grows it increases bulblets. these fall off readily when the plant is pulled, leaving many where there was just one. when i pull oxalis i don't pull at all but rather get a spade underneath it and i throw away all the dirt in the spade. the bulbs are tiny and impossible to pick out, so i accept losing some topsoil.

i inherited a yard full of lawn, and when i moved in my focus was on eradicating the grass. the oxalis was dormant and so i unwittingly spread these bulblets all over my yard when i amended my soil. i have no idea the extent of the damage because it's not even yet fall, but i have stopped planting because i know i have a battle ahead. spraying only extends to the first bulb. all the other bulblets survive it. so digging methodically and regularly seems the only way to go.

mulching with bark is futile. the oxalis will grow right up through it. i have had some success with spreading newspaper between my ornamentals and mulching over it, but i think this will just prevent new bulb growth, not kill it. i still have to weed them from around the crowns of my ornamentals, and i do so every single day. i think if i keep this up for a few years i will probably win. even the most tenacious weeds have only so much stored energy, and if it never sees the light of day, it won't accrue more.

i agree, it's critical not to let oxalis get a foothold. it's not a team player here and growing a dense garden won't stop it. it's been spotted in the wild now and will do damage. spending a half hour a day weeding it out is worth the effort. bulblets will survive composting so i usually save them in a bucket. they survive burning so i'm not sure what the proper way of disposing them is that won't spread them around california.