PlantFiles: Bermuda Buttercup, Yellow Sour Grass, Cape Sorrel, African Woodsorrel, Sour Sob
Oxalis pes-caprae

In the Cali Bay Area here, I don't find this a problem. It's a naturalized exotic and is thus a weed and the deep-rooted tubers are hard to get rid of, but it doesn't spread very fast so I'm fine with it since at the very least it has beautiful charteuse flowers in early spring.

I've encountered horribly invasive oxalis species that spray seeds everywhere and get into everything and choke away everything else, but NOT THIS.

One of my potted palms has one of these growing in it as a volunteer and I'm happy to have it there. Beautiful flowers seasonally and it dies back every summer, unlike some oxalis.

My experience with this plant is largely positive. It arrived as a volunteer, but in three years in my yard it has been well-behaved and has not spread; in fact, one of its advantages is that it seems to choke out the more aggressive, weedy, invasive oxalis. The flowers are pretty and it seems to be easy to keep contained, at least in my yard.

I call it neutral because there are obvious downsides, but it is not without positives. It has edible stems that have a refreshing sour taste, but too much can be poisonous. This is a prolific weed in Southern California, as described by the other negative postings. However, I have found that it was incredibly useful in breaking up the compacted and chemical-laden soil that was left by 50 years of standard-normal turf grass that I inherited when I bought my house. After a few years of letting the sourgrass grow, I found that the soil was greatly improved... and once I put in some native (coastal sage scrub for me) plants, I found it was not that difficult to keep under control. I wouldn't try to cultivate it, but if it grows, I don't think it's nearly as evil as you might think. Also, I've found you can compost the stems (not the roots or little bulbs though!)

My great grandfather used to grow them in his yard by his cactus. They never grew out of that area and didnt seem to be much of a problem for him. Upon cleaning his yard he had to pull them out. He didnt use any of the sifting methods and they never grew back. I'm wondering why if they seem to be such a nuisance for others. I actually would like to start growing them in my own yard but cant seem to find them anywhere.

I lived in California 62 years and never considered this plant a problem. It spreads but slowly. Pulling occasionally controls it and normal mowing will keep it out of lawns. Nowhere as bad as bermuda grass, etc.

I moved to Missouri two years ago and I brought some with me which has been blooming in a pot on a sunporch since mid January. I wish it would grow here on the farm as it is always so cheerful in the spring.

The flowers of this plant are very cheery, especially during the gray early spring. Its invasiveness is a real problem, however, so I'm constantly pulling it out of my flower beds.

The only positive thing I have to say about this plant is that it isn't as hard to deal with as some of the other species of oxalis. It's just very hard, not impossible. For one thing the foliage comes away very easily, and I have found that by persistently removing foliage from bulbs that can't be got at, because they are among tree roots or rocks, over time ( years) the vigour and population is reduced. Disturbing the soil as little as possible also helps. Splitting a clump up through the soil multiplies the problem horrendously. If the roots can be got out, digging down gently along the stems and levering the root and attached bulbils out is worth doing. The earlier the better in the season as they mature very fast . Keep the clump as intact as possible and don't drop any. Dispose of in a way you are certain will kill them, not your compost heap.

Somebody gave my grandmother, now dead, a piece of this plant probably sixty or seventy years ago, in New Orleans. She gave some to my mom, and now that mom is living in an independent living facility I have charge of what our family always called "yellow bells" in my yard. Mom had them in her yard for at least forty years and they multiplied, but were never a nuisance and certainly never spread to the neighbor's yard or even to the front lawn. I had a hard time getting them established here in Mobile, AL--tried 3 times before finally getting them to do well in a raised bed. I think maybe our typically soggy winters rot their bulblets. Now that I know how invasive they can be I will be careful, but right now they are no more than cheerful clumps of bright yellow in the butterfly garden, dying back in the hot summer to return in late fall.

I just spent the day pulling this plant out of my raised bed - the one I had turned over and sifted to get rid of the bulbs last fall. Saying it's successful here is an understatement - it's impossible to get rid of. The one person I know who managed that feat literally moved heaven and earth: she removed the top 2 feet of soil from her yard to get rid of the oxalis.

The worst thing about it is that it chokes off the plants I want to grow, and then when it dies back in late spring it leaves bare ground. It manages to get into my potted plants, between cracks, under pots - it doesn't seem to need light to grow!

Hate it, hate it, hate it.

It is such a pretty plant that I was unable to persuade some folks that the plant they were buying contained a weed. They were not interested in the plant, but the weed!
This has been the major pest of every nursery I have worked at including my own. Once in the soil it is almost impossible to get rid of. Very pretty, but horribly invasive.

It is kind of pretty, the flowers smell nice on sunny days in January/February, and the bees seem to like it.

However, it is an enormous nuisance in wild settings and gardens in temperate climates. The only way to get rid of it is to remove the topsoil down to a foot or two and filter it through a 1/4" mesh strainer. If any single bulb or root segment is left in the ground it will resprout. I've heard when folks have tried to remove serious infestations, the volume of oxalis bulbs nearly equals that of the remaining soil. Each bulb can produce up to 20 bulbils in a season.

Gardens and yards left untended for a season literally fill with it. Plus if you try to compost the stems or bulbs, it will take over your compost pile.

I would love to know why people call this a weed.
Grown in indirect sunlight, in a damp place.
Can be used in landscapping.
Very good to eat, leaves are used in salads, or eaten raw.

Oxalis pes-caprae, a.k.a. Bermuda buttercup, soursob or sour grass, is a South African native, with its fluorescent yellow five-petaled flower. This is a terrible weed in the West that is rapidly overrunning native plants.

The flowers emerge supported by long, almost succulent, tubular stems. The trifoliate leaves, which give the impression of clover, are actually more like folded green hearts, sometimes speckled brown.

Pulling the plant up does not kill it. It is the bulbrils in the ground which send out rhizomes and readily resprout. This plant is highly invasive and should never be planted near any rural or pastoral area.