Butterflies are few and far between if you are an apartment dweller or live in the city. But what if I tell you there’s a gorgeous and low-maintenance plant that may be the perfect butterfly-like thing to keep you company?
An Oxalis Triangularis is a plant with clusters of purple leaves that opens during the day and closes at night. It’s also known as the Purple/False shamrock due to its clover-like shape, but it’s not a true clover/shamrock. Regardless, it’s easy to care for and grows well as a houseplant.
Below, I elaborate more on this plant, along with helpful care tips:
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Table of contents
What is an Oxalis Triangularis?
It is a flowering plant with dark purple clover-like leaves arranged in a triangular shape. This plant belongs to the wood sorrel family and is a native plant from South America, specifically Brazil. As outdoor plants, they produce white or light purple blooms yearly, usually in spring. They can also flower as houseplants as long as they are given adequate care.
However, despite its looks, it’s not a clover. It isn’t part of the true shamrock family native to Ireland called ‘Trifolium’. But it is sometimes sold during St. Patrick’s Day as ‘Purple or False Shamrock’. This is because they do well as houseplants compared to actual shamrock plants that last only a short time. They are also known as ‘Love Plant’, ‘Purple Wood Sorrel’, and ‘Oxalis Regnellii’.
Why do the leaves on my Oxalis Triangularis close up? Like other Oxalis plants, the Purple/False Shamrock closes its leaves and flowers at night and opens up again in the morning. Even during cloudy days, your plant may close its leaves thinking it’s already night! So don’t worry if it does that in the middle of the day – it’s merely reacting to the light intensity in its surroundings.
Despite being called edible, Oxalis Triangularis has low toxicity properties. So if a large amount is ingested, it will cause problems like kidney failure in humans and colic in horses. So please keep your pets far away from it and maybe quell the adventurous streak in you from eating this plant.
What are the Different Varieties of Oxalis Triangularis?
Apart from the widely-known Purple/False Shamrock, there are also variations of the plant out there, such as the green-leaf cultivars:
- Oxalis triangularis subsp. papilionacea
- Oxalis triangularis subsp. papilionacea’ Irish Mist’
- Oxalis triangularis subsp. papilionacea ‘Fanny’
And the purple-leaf varieties:
- Oxalis triangularis subsp. papilionaceae ‘Atropurpurea’
- Oxalis triangularis ‘Mijke’
- Oxalis triangularis subsp. papilionacea ‘Francis’
If you’re not a stickler for details, they all look the same. But regardless of the subtle differences in shades and flecks on the leaves and flowers, their primary care is still the same. This brings us to the next section …
Oxalis Triangularis/False Shamrock Care 101
There are a couple of things this plant needs to flourish in indoor settings, so here’s what you need to keep in mind:
- Plant in loamy, well-draining soil. Purple/False Shamrock isn’t picky about the potting media/ground it grows in. As long as it holds enough water to keep the roots happy and drains excess water, the plant will be content.
- Provide plenty of direct morning sunlight with partial shade from the afternoon glare. While the plant appreciates a lot of light, too much can be bad for its leaves. They may end up scorching or even wilting before going dormant. If you’re growing the plant as an outdoor plant, place it somewhere where it’ll have shade (even in a slightly shade-covered greenhouse) from the afternoon sun.. Also, ensure to rotate the plant daily, so all sides are exposed to the sun.
- Water once a week at the soil level, only after the first 1-2 top inches of the soil dries out. It’s very easy to overwater this plant, so check the potting media/ground before watering. Doing the knuckle test as explained in this 4 Basic Houseplant Care article is advisable, but if you want a quick, dirt-free way to do it, I highly recommend using a moisture meter. You can use this to check multiple plants in one go before watering (or not!) all your plant babies without overthinking the whole process. I use this exact soil hygrometer sold by Amazon, which has succeeded in keeping me from un-aliving my plants again and again. It has about 4.4 stars with solid 31, 288 ratings!
- Feed once a month in spring and summer using diluted liquid fertilizer. Alternatively, you can do it once every three months so the plant will still get a nutrient boost. An all-purpose formula for houseplants is sufficient. But even if you skip this step, the plant will have no problems growing.
- Let the plant enter its natural dormancy in late summer or fall. Your Purple/False Shamrock will start to droop and die off entirely later in the year, but that’s just its way of going to sleep. It is usually triggered by shorter days and cooler nights. When this happens, stop watering the plant, remove all shriveled parts, and store it somewhere cool and dark. In 1-3 months, it’ll come back to life as if nothing happened. Then you’ll have to water it slowly and move it to a sunny area to develop more. Notably, some people observe that their indoor Purple/False Shamrock doesn’t do this, and it’s still fine. But if you’re unsure why it is wilting out of nowhere, this article on ‘Drooping Oxalis Triangularis’ may help you detect the problem.
Additional Care for Growing Oxalis Triangularis
Now, you’ve pretty much covered the basic needs of the plant. However, there is some minor maintenance you have to do to keep your Purple/False Shamrock happy in your home:
- Repot the plant every two years in spring. Oxalis Triangularis grows moderately fast, especially if it has everything it needs to develop well. Simply use a slightly larger pot than the previous one, or you can propagate it into several new pots.
- Propagate the plant by root division in spring. You can do this any time, but after its natural dormancy is best. You only have to split their thick finger-like roots into pieces and plant them. It’s a straightforward process of plopping it in soil and watering it lightly. Before you know it, you’ll see the stems pop right up. You follow the instructions on how to divide the plant in this propagation article.
- Prune old and damaged leaves only. Purple/False Shamrock doesn’t need much pruning as you want it to be as bushy as possible to look its best. When there are only straggly bits, it’s quite an unimpressive plant to look at. But if you’d like to trim some off to shape its look, only cut off 1/3 of its overall foliage.
- Do a weekly pest & disease check. Oxalis Triangularis is prone to infestations and infections as a houseplant. Simply because there’s no wind or predatory bugs to keep them away. Typical pests that bother it are spider mites, aphids, whiteflies, and mealybugs. But you can get rid of them by following the instructions in this houseplant pest article.
Frequently Asked Questions about Oxalis Triangularis
There are four things to keep in mind when taking care of an Oxalis Triangularis:
Plant it in well-draining soil.
1. Give it plenty of direct sun with protection from the afternoon glare.
2. Water it weekly only after the top 1-2 inches of the soil dries out
3. Fertilize it once a month in spring and summer.
An Oxalis Triangularis can be both an indoor and outdoor plant, provided it grows in well-draining potting media or soil. The difference is you won’t baby it too much in a garden as it will grow prolifically with the amount of sun it gets. But that doesn’t mean it isn’t an excellent houseplant to have too.
A nearby window with sheer curtains is an ideal place for an Oxalis Triangularis to grow indoors. But outdoors, grown among slightly taller plants will help shade the plant from the afternoon sun. Either way, any sunny place is suitable for the Purple/False Shamrock to develop.
Oxalis Triangularis needs weekly watering only after the soil dries out at the top 1-2 inches. It can usually handle drought periods once it has matured. So even if you forget to water it, it’ll bounce right back if it’s underwatered. But the one thing you should avoid is overwatering because that’s a little harder to fix. You also need to direct the water to the soil only and prevent splashback to the leaves.
Ensure plenty of direct sunlight on all sides of the Oxalis Triangularis to encourage bushy growth. If the plant only receives sun on one side, it’ll grow heavily there. So rotating it every day will allow the plant to grow evenly.
Root rot from overwatering and fungal pathogens can cause an Oxalis Triangularis to die unless it is dealt with asap. Usually, the plant bounces back quickly once the underlying problem is taken care of. But this is not to be confused with the plant’s natural dormancy period. The entire plant may look like it died, but the roots are very much alive in the soil. However, if the roots have rotted or are infested/infected, then the plant is a goner.
Oxalis Triangularis’ bulb/corms grow continuously as the entire plant develops. They don’t necessarily “multiply”; instead, they grow in length and sections from the original tuberous root. These can be propagated by breaking/dividing them into pieces.
It’s unnecessary to cut back an Oxalis Triangularis. Instead, dividing the roots is better to avoid overcrowding in the pot. However, if the goal is to trim the plant to a particular look, keep in mind only to cut 1/3 of the overall foliage.
Natural dormancy may be the cause of a drooping purple Oxalis Triangularis. This is a yearly occurrence as the plant’s leaves die off, leaving behind healthy tuberous roots. However, there may be cases where it is caused by improper care, which you can read in this ‘Drooping Oxalis Triangularis’ article.
As a perennial plant, Oxalis Triangularis grows back yearly after its natural dormancy period. The plant can live for a very long time, provided it receives the best care. Some have even used them as family heirlooms passed down from generation to generation.
It’s ill-advised to mist an Oxalis Triangularis as this will allow pathogens to latch onto the plant and cause diseases. This is also why it’s important to only water the plant at the soil level, so the levels stay dry in the process. “Misting” to increase humidity levels doesn’t work, as there are better ways to do so. There needs to be a constant mist in the air to significantly raise the surrounding humidity – so unless you have all day to spritz your plant every 30 seconds, a humidifier is your best option.
Stop watering and store the Oxalis Triangularis in a cool, dark place when winter arrives. Get rid of all the dead leaves and stems before storage too. It should take about 1-3 months before the plant starts to exhibit new growth. By then, begin watering the plant lightly and give it some sun to get it developing again.
All in all, an Oxalis Triangularis, aka Purple/False Shamrock, is a pretty chill houseplant that can flourish anywhere! So if you don’t want the fuss of having a butterfly garden, this plant may just be the next best thing for you. Happy planting!
- The Care and Feeding of “Shamrock” Plants. (n.d.). Extension.umn.edu. Retrieved October 13, 2022, from https://extension.umn.edu/news/care-and-feeding-shamrock-plants
- The care and feeding of purple-leaf shamrocks. (n.d.). MSU Extension. https://www.canr.msu.edu/news/the_care_and_feeding_of_purple_leaf_shamrocks
- Oxalis triangularis (False Shamrock, Love Plant, Purple Shamrock, Purple Wood Sorrel) | North Carolina Extension Gardener Plant Toolbox. (n.d.). Plants.ces.ncsu.edu. https://plants.ces.ncsu.edu/plants/oxalis-triangularis/
- Growing shamrocks indoors. (n.d.). Hortnews.extension.iastate.edu. Retrieved October 13, 2022, from https://hortnews.extension.iastate.edu/2019/03/growing-shamrocks-indoors
- Searching the Garden.org Plant Database. (n.d.). Garden.org. Retrieved October 13, 2022, from https://garden.org/plants/search/text.php?q=oxalis+triangularis
- Oxalis – Biology Teaching Greenhouse. (n.d.). Sites.berry.edu. Retrieved October 13, 2022, from https://sites.berry.edu/cborer/inventory/oxalis/
- Oxalis: Shamrock’s Imposter (David Trinklein). (n.d.). Ipm.missouri.edu. Retrieved October 13, 2022, from https://ipm.missouri.edu/MEG/2019/3/oxalis/index.cfm