Oxalis Triangularis Care (Purple Shamrock)

The false shamrock or purple shamrock is an exquisite, eye-catching ornamental plant. It features stunning dark foliage that is a cross between the color black and purple. 

Oxalis Triangularis

It has its origin tied to the deep tropical regions of Brazil and a few other countries around South America. 

The purple Oxalis Triangularis is a rhizomatous plant that hails from the Oxiladaceae family and belongs to the Oxalis genus.

Its flowers and leaves can be eaten, as they are even regarded as proper components for dressing or decorating salads. 

The leaves of the Triangularis Oxalis plant are trifoliate, and as such, resemble the leaves of species in the Trifolium genus, this is why the Oxalis variety is called ‘False Shamrock’

Wherever the Oxalis Triangularis plant is placed, whether its an indoor living space or a garden, it provides a divine aesthetic feel that is attractive from whatever angle it is being viewed from. 

Botanical NameOxalis Triangularis 
Common NamesPurple Shamrock, False Shamrock
OriginSouth America
Plant TypePerennial, herbaceous plant 
Full SizeCan grow to 1 ft tall and 2 ft wide 
Sun ExposureFull sunlight to partial sunlight
Soil TypeWell draining, loam soil 
ToxicityEdible, can cause discomfort when eaten in large quantities

Oxalis Triangularis Care

For a beginner, getting an introduction into the world of gardening, the Oxalis Triangularis might not be the best start. 

However, with the right knowledge of the basic Light, soil and watering, pruning, and temperature requirements of the exotic plant, It should become an easy plant to care for. 

Oxalis Triangularis Light Requirement 

It is recommended that you provide your Oxalis Triangularis plant with sufficient access to direct sunlight.  This is essential for proper growth. 

Oxalis Triangularis Light Requirement 

The plant should be kept with direct sunlight for a maximum of 6 hours, after which you provide adequate shade to the rare houseplant. 

Excess direct sunlight on the leaves of the Oxalis Triangularis could be harmful as well as provide too little sunlight to the houseplant. This is why you must learn to alternate these two light intensities. 

Place the potted plant in a room that meets the light requirement when indoors. Placing it right next to a window would be perfect. You could make use of a light curtain to shield off the sun’s harsh rays if the need be. 

Oxalis Triangularis Water Requirement

Although the Oxalis variety isn’t a complete drought-resistant plant, it can still survive long hours without water.

What you should take extra care in avoiding is overwatering the Oxalis Triangularis plant. Soggy soil could open the roots up for fungal attacks like root rot. 

The aim when watering should be to keep the soil moist at all times, not soggy, but moist. You can achieve this by feeling the topmost part of the soil with your finger before watering.

If the top feels dry, then you can proceed to water the plant’s roots. Watering once a week would be ideal. However, because the plant goes dormant during winter and fall, it is recommended you water your oxalis plant once in two or three weeks. 

Room temperature water should be best used when watering, as water that is too cold, could cause shock to the plant’s delicate roots. 

Oxalis Triangularis Soil Requirement

Because the Oxalis Triangularis doesn’t like its roots being soggy, it is best advised you provide it with soil that is blessed with great water draining ability. 

Oxalis Triangularis Soil Requirement

Whatever potting mix is used, must be light so as to allow the delicate roots to breathe with ease. An appropriate soil mix to achieve this would be one part peat, one part loam soil, and a part potting soil.

Fertilizer could be added to the soil mix, however, the plant would require less fertilizing as it grows. 

In addition to having great water draining ability, the soil used should be able to retain water, good enough to remain moist for long hours. 

Oxalis Triangularis Temperature and Humidity Requirement         

The exquisite house plant does not require high humidity levels to thrive. To keep it looking good, the average indoor humidity should be fine. 

When it comes to temperature, a range between 60 degrees Fahrenheit and 74 degrees Fahrenheit would do. If the temperature goes above 75 degrees Fahrenheit, you risk sending the plant to an Oxalis Triangularis dormancy period. 

If this happens, you should consider stopping the frequency at which you water the plant, prune off its dead leaves and move to a dark but cool environment for a few weeks. 

Oxalis Triangularis Fertilizer Requirement

How often you choose to fertilize your Oxalis Triangularis depends on whether fertilizer was added to the soil mix. 

Oxalis Triangularis Fertilizer Requirement

If fertilizer was added to the soil mix, then you should not have to bother about fertilizing your exotic house plant for a few months. 

Should you choose to keep fertilizing your Oxalis Triangularis despite it being added to the mix, then be generous and scatter the slow-release fertilizer granules all over the soil. Following this watering the plant.

In situations where fertilizer was not added to the mix, a liquid soluble fertilizer should be used every 2 to 3 weeks. This should be added when you water the plant.    

Be careful not to overdo it with frequent fertilizing, as it could cause more harm than good,  so it is advised that you deep water the plant’s soil often. Ensure that the water passes through the drainage holes at the base of the pot.

Oxalis Triangularis Propagation

Propagating Oxalis Triangularis can be done by offset separation. This would help in growing new plants. 

Oxalis Triangularis Repotting Requirement

Oxalis Triangularis Repotting Requirement

The Oxalis Triangularis would need to be repotted off (once or twice a year) to a larger pot size to accommodate the growing plant. A fresh soil mix would be needed once this happens.

Oxalis Triangularis Pruning Requirement  

The ornamental plant does not require frequent pruning, However, pruning would be required to get rid of dead leaves and to rescue the plant from dormancy. 

When pruning does ensure you sterilize or tools to be used before using them. And be careful so as not to damage the plant’s stem. 


The leaves of the Oxalis Triangularis are edible. But they can be toxic to humans and pets if eaten in large quantities, They could induce vomiting and tummy discomfort. 

Common Health Problems of the Oxalis Triangularis

Oxalis Triangularis varieties are tough plants. However careless overwatering and pests can open up the exotic houseplant to a few health problems, a few of these are; 

  • Roots Rot
  • Rust
  • Powdery Mildew
  • Spider Mites
  • Mealybugs

Frequently Asked Questions

Where can I buy oxalis triangularis?

Oxalis Triangularis bulbs are sold in numerous stores in the United States. You can order from online stores like Etsy and Amazon. 

Does oxalis triangularis spread?

No, the Oxalis Triangularis grows in a compact way that limits spreading

Do oxalis triangularis bulbs multiply?

You can reproduce the Oxalis Triangularis from its bulbs

How long does it take Oxalis to grow?

It takes an Oxalis Triangularis plant a full 8 to 10 weeks to form its purple shamrock leaves. 

How do you keep Oxalis bushy?

Providing the luxurious plant with adequate sunlight and a cool temperature would keep it growing full and well.