The Oxalis genus is most commonly known for the shamrock-shaped plants that become widely available around mid-February for people to buy in time for Saint Patrick’s Day!
While these beautiful plants are one that I personally love and recommend people to try, the Oxalis genus has lots of interesting plants beyond the ones we see for St. Patty’s Day and has a pretty engaging story to tell about itself.
In this post we will cover the popular False Shamrock plant, interesting info about the genus, and some of the lesser-known species worth checking out!
Oxalis plants are everywhere and they are edible
Oxalis are found in many places around the world, but the largest diversity of Oxalis species are found in Southern Africa and South America.
The name, Oxalis, comes from the Greek word for acid, due to the acidic taste of the plant’s leaves and flowers.
As you may have guessed from where it gets its name, Oxalis has been consumed by people throughout history. It was (and still is) used by foragers as an easy-to-find plant to provide sustenance.
Despite its long history of being eaten, there is some debate about the toxicity of Oxalis. It turns out that oxalic acid is slightly toxic to humans. However, someone would have to eat a very large quantity of Oxalis in order to feel the effects. Oxalic acid is also in many other foods we commonly eat like broccoli, spinach, sweet potato, and even celery.
While Oxalis may be considered generally safe for humans, it is considered toxic for our pets (even in small quantities)!
Photo credits from left to right, top to bottom:
2. chengte, https://www.inaturalist.org/observations/29695364
3. don_k, https://www.inaturalist.org/observations/32833709
5. guille, https://www.inaturalist.org/observations/9257405
6. janinegreen, https://www.inaturalist.org/observations/25985234
Oxalis are loved by some and hated by others
Though many of us covet Oxalis triangularis and Oxalis regnellii (False Shamrock Plants) for their beauty as houseplants or garden ornamentals, Oxalis are seen by many to be a weed that must be controlled or eradicated.
Why? They are incredibly prolific and hard to control. The plants require very little to stay alive and when those conditions are not met they simply go dormant and wait for the right conditions again to continue growing.
This has allowed both native and invasive species to thrive around the world, much to the dismay of people who attempt to keep manicured lawns free of Oxalis.
I find Oxalis corniculata frequently in our lawn, but I welcome their little leaves and yellow flowers. Some O. corniculata planted itself in a container last year where I was growing parsley and I let it grow the entire summer there, filling in around the plant. 🙂
Since Oxalis attract pollinators and I like to garden specifically for pollinators, this plant was a wonderful addition to my garden.
However, Oxalis are so prolific that there are 3 species that are considered invasive in the United States: Oxalis debilis subsp. corymbosa (Pink Woodsorrel), Oxalis pes-caprae (Bermuda Buttercup), and Oxalis stricta (Common Yellow Woodsorrel).
The first, Oxalis debilis supsp. corymbosa var. ‘Aureo-Reticulata’ is sold as a highly desirable houseplant due to its striking foliage and vibrant flowers (pictured below).
The most popular of all the Oxalis is the False Shamrock plant
Oxalis triangularis or Oxalis regnellii subsp. triangularis are sold as False Shamrock plants. Why are they false shamrocks and not the real thing? True Shamrocks are a type of clover (Trifolium repens). While both the clover and these Oxalis species share three leaves emerging atop each stem, they reside in a different genus, and have differently-shaped leaves and flowers!
The False Shamrock – Oxalis triangularis
The Real Shamrock – Clover – Trifolium repens
False Shamrock Care:
Oxalis triangularis is commonly available in both purple and green varieties and is pretty easy to care for. They can do quite well in lower light windows as well as pulled a little back from highly-lit Southern exposures.
The biggest part of their care is letting them teach us how often to water them. Their leaves and stems are very delicate and unable to hold much water; as such they wilt quite easily out of thirst.
The good news is that they perk right back up if watered promptly. I try to water mine before they wilt (when the first inch of soil is dry), but sometimes I don’t catch them in time and it hasn’t been a problem so far.
I rotate my Oxalis very often – more often than any other plant I own. They are extremely capable of moving and stretching toward the light, so if you prefer a plant that doesn’t lean to one side rotating is necessary! You’ll be able to see how much they move in the timelapse video below!
I use a well-draining soil, but not quite as well-draining as for my more succulent plants since these guys need a little extra moisture. They are planted in ceramic or plastic pots so the pot isn’t going to be wicking moisture from the soil. I’m sure you could also successfully keep Oxalis in terracotta or cement; it would just require more water.
Below is one of my Oxalis. It’s wilted heavily from lack of water. I watered it thoroughly and the next morning it looked good as new!
The dance of the Oxalis
Oxalis, besides looking quite beautiful, also move on a daily basis. After the sun goes down in the evening, Oxalis close their leaves to conserve energy until light levels are high enough for them to open and begin photosynthesizing again.
Here’s a timelapse of Oxalis triangularis moving throughout the day.
Growing Oxalis from Bulbs
Many Oxalis grow from bulbs. A few Oxalis bulbs can produce a full pot in a pretty short amount of time. Growing them from bulbs is often cheaper than purchasing a plant, particularly if you want to try growing some of the less common species or cultivars.
If you are interested in trying to grow some from bulbs yourself, here is a really wonderful video that goes through how to do that step-by-step!
The instructions I follow is to plant my bulbs in a well-draining mix and water them as if it were an Oxalis that has foliage already. I keep the pot in a brightly lit area and just watch for some sprouts. As you can see in the video below also, these little guys are really quick to grow and are very rewarding!!
Let me know if you decide to try growing some Oxalis bulbs and how it goes for you!
Oxalis includes some very fascinating, fairytale-like species
Here are just a few of the amazing species of Oxalis beyond those we typically see in stores. Which one is your favorite? My current favorite is definitely O. palmifrons, as it looks like this amazing spiral of miniature trees. I think I am going to try to grow this one from bulbs once Spring comes!
Which Oxalis is your favorite? Do you successfully keep any in your home? Tell us in the comments below! 🙂
Resources used for this article: Click to read last week’s article: Are Tissue-Cultured Houseplants of Poor Quality?
Click to read last week’s article: Are Tissue-Cultured Houseplants of Poor Quality?