Oxalis Tetraphylla Care – The Ultimate Iron Cross Plant Care Guide
This is an ultimate guide on how to grow and care for oxalis tetraphylla iron cross plant indoors.

Looking for an ultimate care guide for Oxalis tetraphylla plant?
Well, you are at the right place. This is the only article you need to grow oxalis tetraphylla or iron cross plant in your indoor or outdoor garden.
We cover everything related to the plant including,
- What is Oxalis Tetraphylla?
- Oxalis Tetraphylla Varieties
- Oxalis Tetraphylla Appearance
- Oxalis Tetraphylla Care Guide
- Pruning Oxalis Tetraphylla
- Oxalis Tetraphylla Propagation
- Oxalis Tetraphylla Toxicity
- Lot’s more.
Let’s get started.
What is Oxalis Tetraphylla?
Oxalis tetraphylla is a bulbous herbaceous, perennial plant that belongs to the Oxalidaceae family (wood sorrel family) of the Dicotyledonae class from Mexico. It belongs to the Spermatophyta phylum and Angiospermae subphylum.
Oxalis tetraphylla is commonly named the lucky leaf, good luck leaf, lucky clover, four-leaf sorrel, and four-leaf clover.
Oxalis tetraphylla belongs to the Tetraphylla species, and its general synonym is Oxalis deppei, Oxalis esculenta, and Oxalis pseudotetraphylla.
Though Oxalis Tetraphylla is a native of Mexico, it is well naturalized and cultivated in many parts of India and other parts of the world. This plant also has ornamental properties and is often used as an edible resource.
The flowers and their leaves consist of a lemon-like flavor that may interfere in the taste and absorption of certain nutrients like calcium.
Oxalis tetraphylla plants act as a lucky charm, especially on New Year’s Eve when the color of the flowers is given significant importance.
Oxalis Tetraphylla Varieties
The two varieties of oxalis tetraphylla are commonly called as Iron Cross and Alba lie essential charms.
Iron Cross plant grows between June – October with large umbels of pink flowers and has red and brown markings on the leaves.
Another variety, Alba, has white flowers with four-leaf foliage.
You can create a pattern of oxalis tretaphylla plants by combining Alba with Iron Cross plants.
Oxalis Tetraphylla Iron Cross Appearance
Oxalis tetraphylla can generally be identified with stolons and bulbs. Its height can range from 15 to 40 cm. Oxalis tetraphylla consists of four to five seeded capsules, 5-12 mm long.
Oxalis tetraphylla can be identified by its four-split green leaves with a dark center. Its shape is like a spread hand divided into four inverted heart-shaped leaflets.
The leaves of the plant are often are used as edible resources, either raw or cooked.
However, it is consumed in moderation as it can turn poisonous if consumed in excess. Oxalis tetraphylla is a stemless herb with no rhizome or runners. The color of Oxalis tetraphylla flowers is classified into mostly white, light, and dark pink.
Its flower petals are generally five with a diameter of up to 2 cm. The Oxalis Tetraphylla flowers are usually borne in umbels of 6-25 flowers, of which petals are oblong spoon-shaped, apex rounded, hairless with greenish base.
Flower petals are approximately 1.5-2.5 × 0.5-1.2 cm
Oxalis Tetraphylla Care
Oxalis tetraphylla Iron Cross is a plant suited in most types of soils and can be placed outdoors and indoors.
It prefers bright light for its survival and grows best in temperature between 18-30 degrees Celsius whereas watering and fertilizing are also not bothering.
Soil Requirements For Oxalis Tetraphylla
An ideal soil type of the Iron Cross plant are clay, chalky, loamy, and sandy; however, it can grow and tolerate most soil types.
The soil drainage of Iron Cross plant should be moist but well-drained with soil pH levels of Acid, Neutral and Alkaline nature. The accepted pH levels of soil are 6.1 – 6.5 (mildly acidic), 6.6 – 7.5 (neutral), and 7.6 – 7.8 (mildly alkaline).
Iron Cross plant can spread up to 0.15m after 2-5 years and can demand repotting after it doubles its size or once every year. Iron Cross will grow its best if the soil has organic matter like coco coir, perlite, and vermiculite.
It will help in better drainage and grow the plant. However, adding a little perlite to the regular pot of soil from the store can also help Iron Cross plant with better drainage.
Light Requirements
Iron Cross plant prefers bright direct or indirect sunlight and is not suited for low-lighted conditions.
It can grow by its full potential when placed in partial shade or full sun and exposure is sheltered.
You can pot it in your garden or place it in your room. If you pot Iron Cross plant as your room plant, you must ensure it is less than one foot from the south-facing window. This will ensure it receives enough light to survive.
If you place Iron Cross in a sunny place, it will grow to its full potential when the temperature is between 18-30 degrees celsius. In winter, the active radiator should be placed away from the plant as it does not prefer dry heat.
Whereas, in the middle of May, Iron Cross plant prefers a half-shaded place with bright light, protected from wind and rain.
Temperature & Humidity
Iron Cross grows best in temperature between 18-30 degrees celsius (65-85 degrees Fahrenheit).
However, it can also survive the autumn when the temperature drops by placing it indoors.
It can also survive the cold winters when the pot is placed in a dark room with a temperature between 10-15 degrees celsius—however, it’s best not to let it go below 15 degrees celsius (60 degrees Fahrenheit).
It can also survive in any humidity level; even normal room humidity will also work for Iron Cross plant.
Watering Oxalis Tetraphylla
Generally Iron Cross plant requires 0.8 cups of water every nine days when it doesn’t get direct sunlight.
However, your plant should be watered every 1-2 weeks and allow the soil to dry out between waterings.
It is ideal to water more when in direct sunlight and water less in less light. It is advised to use soft water, which does not increase the pH value in the substrate and decreases the uptake of nutrients and leaf chlorosis.
Filtered rainwater boiled tap water is particularly suitable to water oxalis tetraphylla iron cross plant.
Fertilizing Iron Cross Plant
Oxalis Tetraphylla Iron Cross plant requires low nutrients and doesn’t require added fertilizers. Replacing the soil every once a year is enough to provide the plant with demanding nutrients.
However, the plant can be fully satisfied if you fertilize the soil with a standard liquid fertilizer every four weeks between April and September.
Also, it is advised not to use the fertilizer on dry soil or to water it first with lime-free water or clear water.
In winters, some portion of the plant may die if not given enough sunlight, but it can be grown back upon providing a dose of fertilizer and more light.
Best Place To Grow Iron Cross Plant
Oxalis tetraphylla Iron Cross can be grown with USDA Hardiness Zones 7a-10b outdoors and UK hardiness of Hardy (H4). The plant is best suited to grow in containers or sheltered rockeries and borders.
If situated in frost-prone areas, it is advised to place Iron Cross plant indoors with a bright windowsill, greenhouse, or conservatory. Iron Cross will bloom best while in these places in late spring or early summer, mid-summer, late summer, or early fall.
Oxalis tetraphylla Iron Cross’ natural habitat is to grow where the temperature is between 18- 30 degrees celsius (65-85 degrees Fahrenheit). From early summer, its foliage is paired with pink and tabular flowers.
This makes it an ideal decorative pot plant that can be used indoors. The iron cross plant can also be placed outdoors and can be equally effective as ground cover in troughs and rockeries.
Pruning Oxalis Tetraphylla
Pruning or cutting off faded flowers and dried leaves is necessary to preserve the plant’s well-groomed appearance. The pruning of the faded flowers and leaves should be done individually or after the blooming period is over.
You should clean out the flowers promptly and avoid Iron Cross plant investing in unnecessary seed production rather than rigorous plant growth. However, foliages can be removed anytime to prevent damages, discoloration of leaves, and maintain the plant size.
You can regularly prune for faded flowers and dried leaves. However, only in the case of overwintering when the plant becomes completely yellow should you cut all parts of the plant down.
This exercise stimulates new growth for the plant. Until then, the bulbs of Iron Cross use all the remaining nutrients and create reserves for the next season. However, it is suggested that the iron cross plants should not be pruned when the first frost arrives.
It is because the perennial plants take time to ‘harden off’ or prepare for winter.
However, the plants are easy to clean when they die on the ground by simply cutting them to about 4 inches (10 cm) above the ground.
This makes the plumes and foliage an ornamental grass creating a fascinating winter landscape. After the previous pruning process, leave the entire plant for the winter, and before new growth starts, again cut the plant to the ground level in early spring.
These perennials should be dug up every 3 to 4 years ensuring iron cross’ healthy growth. It also encourages future blooming and expansion of the garden by new plants.
However, in the end, it is also suggested not to use cuttings of the plant as green fodder for hamsters, rabbits, and small animals.
Oxalis Tetraphylla Propagation
The Iron Cross plant can be propagated by two means – division, seed or bulblets, and cuttings. This is studied below and should be done following the step-by-step method.
In the division method, the plants are made to produce stolons, bulbs, suckers, rhizomes, and tubers. Follow the below instructions for successful propagation:
- Locate a successfully 6-8 inch or larger growing mature iron cross plant in the spring.
- Take a shovel and place it 4 inches from the base of the stalks and slide it down to about 8 to 12 inches deep.
- Remove the oxalis tetraphylla by lifting the oxalis clump from the soil.
- Cut the root ball into two halves or multiple segments. Note that each segment has a rhizome root and a growing green stalk.
- Fill the loose, rich fertile soil above the drainage and place each piece in its pot at a depth of 3 cm (1”).
- Place the pot in half shady location.
- Water the roots daily until the soil is evenly damp 6 to 8 inches deep.
- After six weeks, when stock is consumed in pre-fertilized soil, use the fertilizer.
- Take ongoing care of the plant until the soil starts to feel slightly dry.
Another method, bulbets, is also used in which the mother plant tries to aftergrow. This propagation method does not grow as fast as the division method but will grow in 3 to 4 weeks.
The mother plant produces small bulbs that are seen in spring while repotting. Below are the instructions to follow for successful propagation:
- Fill small pots with well-drained potting soil
- Take a disinfected knife and cut off the bulblets
- Place them in the small pots that we made in step 1
Another method is cutting, in which you can cut off the shoots and grow in the glass filled with water. This is the simplest of all methods.
Through this method, you can notice the roots sprouting and reaching a sufficient length within 2-3 weeks. Follow the detailed instructions from below:
- Cut off the healthy and leafy shoots amid the growth phase of the plant
- Place them into a glass of soft water
- Add a pinch of charcoal to prevent decomposition
- Place the glass in a half-shady location with sufficient access to light
- Replace the water regularly
You can later place the rooted shoots in small proportions in small pots filled with loose and permeable soil and sprinkle them.
Iron Cross Plant Toxicity
Oxalis tetraphylla Iron Cross plant contains a high level of oxalic acid and oxalate salts which can cause harm if consumed in large quantities. It is generally suggested to keep pets and children away from the plant.
Though this plant is often used for medicinal purposes, it is strictly advised to people with rheumatism, arthritis, hyperacidity, kidney stones, and gout to cautiously use the plant.
It should not be in excess if taken in diet and should be cooked first if advised by a medical practitioner. This reduces the quantity of oxalic acid in the leaves and makes them less poisonous.
Especially people with the above-mentioned diseases are asked to take it with caution since it can aggravate their condition by leading to nutritional deficiency.
If ingested in large quantities, it can result in poisoning in dogs, cats, and humans. The plant contains soluble calcium oxalates that are absorbed from the gastrointestinal tract, which contracts with the body’s calcium level.
This results in a sudden drop of calcium in the consumed body and can result in rare or acute renal failure. Signs of this type of poisoning can cause problems like vomiting, diarrhea, bloody urine, inappetence, lethargy, weakness, tremors, and changes in thirst and urination.
Common Problems Of Oxalis Tetraphylla
There can be many problems of Iron Cross plant like yellow leaves, mushy stems, crispy edges, brown leaves, or no new growth.
This might happen due to unfavorable climatic conditions, under or overwatering, lack of sufficient light, unfavorable use of soil and fertilizers, etc.
The most common problem is the yellow leaves and mushy stems. The reason for this problem is overwatering and root rotting. To correct this, you should keep the plant where it gets sufficient sunlight and try not to overwater it.
If your environment has low humidity that what is needed, then your oxalis tetraphylla may experience problems like wilting brown leaves and crispy edges. Underwatering can also trigger the same.
If placed indoors, you should place it near 5 ft near the window where it can get sufficient bright light and water it 0.8 cups every nine days.
If you are experiencing no new growth in the plant, it is because your plant has gone dormant. It is suggested to not water then and wait for the signs of new growth. Once the plant shows the signs, you can increase the frequency of watering.
However, if dormancy is not the reason, you should look if the plant is getting enough moisture. This depends on poor watering techniques, poor lighting, poor potting mix, and pests.
To correct this, you can reanalyze your frequency of watering (remember iron cross plant demands water in less frequency), quality of water, the position of the pot (if placed indoors), adequate exposure to sunlight, and repotting the plant.
Another problem is plant becomes leggy or bending from one side.
If the plant is not provided enough light, it may bend in the direction of the light. It demands the right position to place the plant where it gets sufficient light.
Most common garden pests like spider mites and rust may affect your plant. To avoid this, fertilize your plant when you see pests and ensure your plant gets sufficient sunlight.
Similar Oxalis Varieties
Wrapping Up
Oxalis tetraphylla Iron Cross is a dynamic plant that can survive when given adequate light, water, temperature, and soil requirements.
The pruning and propagation of the plant are some aspects that can define the growing potential.
However, you should note that this plant also carries some toxicity.
Sources
To back up the information we provide in our articles, the Plantials team only uses high-quality sources published in peer-reviewed university or scientific research journals.