Oxalis plants—sometimes referred to as shamrocks and love plants—typically grow up to a foot (30 cm) tall and wide. However, they tend to grow more laterally when planted in the ground. If you want your plant to grow upright and bushy, you’ll first have to address its basic care requirements.
Here are a few excellent practices you can use to make an oxalis plant more bushy:
- Provide your oxalis with bright, indirect sunlight.
- Water your plant deeply but infrequently.
- Maintain moderate temperatures throughout the year.
- Fertilize the plant during the growing season.
- Maintain moderate humidity levels.
- Regularly prune your oxalis plant.
- Repot the oxalis every two to three years.
Most people grow oxalis plants to decorate their homes and beautify their gardens, but it’s not uncommon to use the plant as food and medicine. Regardless of your reason for having the plant, this article will provide helpful tips to get the most out of your oxalis.
1. Provide Your Plant with Bright, Indirect Sunlight
Like every other plant, oxalis needs plenty of sunlight to photosynthesize and flourish. However, you’ll need to be cautious with the sunlight, as overexposure can seriously damage the plant and cause its leaves to wilt.
You should also avoid exposing the plant to the scorching midday sun. Oxalis might seem resilient, but they’re not as drought- or heat-tolerant as cacti and succulents. The purple variety may even turn white from intense sunlight.
About 6 hours of gentle morning sun should do if you want to get full, beautiful, and bushy plants. Choose a shadier spot or install shade covers if your garden receives too much midday or afternoon sun.
Growing oxalis under indirect sunlight means you can get all the benefits of the sun without worrying about burns—even in the middle of the afternoon. Tarps, tree branches, and bigger plants can also help provide shade if you have outdoor oxalis plants.
You can observe the leaves of your oxalis to ensure your plant is getting the right amount of sunlight. Healthy oxalis leaves follow light sources throughout the day and spread when bright light is shining on them. Stationary leaves mean you need to relocate your plant immediately.
Alternatively, you can grow your potted oxalis indoors. Place the pot about 4-8 feet (1.2-2.4 m) from a bright window and rotate the plant by 90-180 degrees every week to ensure the plant remains bushy.
2. Water Your Plant Deeply But Infrequently
You don’t need to overwater oxalis plants to make them flourish. Oxalis plants have bulbous roots that can store a bit of moisture and provide the plant with some degree of tolerance to dry soil. However, it’s best not to let the soil become bone-dry.
Watering your oxalis deeply every 5-7 days is usually enough to keep it hydrated during spring or fall. Of course, this can vary depending on where you live and the quality of your soil. A good rule of thumb is to wait until the top 2-3 inches (5-7.6 cm) of garden soil or half the potting soil is dry before watering again.
Overwatering can cause root, bulb, and stem damage—resulting in leaf loss and seriously damaging your plants. It can also lead to fungal infections, such as powdery mildew and rust fungus, which can cause damage to your plant.
I recommend you water enough to moisten the top 6 inches (15 cm) of the garden soil. For potted plants, water gradually until the excess drains out of the drainage holes.
You might need to water more frequently during hot summer and less often during colder months. Just ensure you don’t underwater your oxalis, or they’ll dry out. Remember to avoid overhead watering. Pour room-temperature water near the roots for best results.
3. Maintain Moderate Temperatures Throughout the Year
Oxalis plants like moderate environmental conditions if you want them to be bushier. They’ll wilt if it gets too hot, and they won’t produce a lot of leaves if the temperature falls below 50 °F (10 °C). So, it’s best to keep them between 60 and 75 °F (15.6 and 24 °C) if you want bushy plants.
I recommend you ensure the temperature never rises beyond 80 °F (27 °C) to get lovely, healthy oxalis plants. Ensure you don’t expose your oxalis to temperatures below 40 °F (4 °C), as this can be fatal.
You can move your potted plants indoors and cover outdoor plants with burlap sheets or apply about 4 inches (10 cm) of organic mulch like straw or wood chips to maintain optimal temperatures during winter. In contrast, a good-quality shade cover and regular watering will cool your oxalis during summer.
Remember to keep an eye out for fluctuating temperatures as often as possible. To get accurate temperature readings, you can use a simple indoor or outdoor thermometer.
4. Fertilize the Plant During the Growing Season
Oxalis prefer moderate resources if they grow, thrive, and become bushy, so you’ll need to be careful when fertilizing the plants. I recommend you use liquid fertilizer once or twice a month for best results. You can fertilize as you water to make the process easier.
Ensure you never fertilize your oxalis more than twice a month, as repeated fertilizer treatments can cause salt buildup to burn the plants. Remember to take great care when fertilizing, and don’t use too much during a session.
I never had a problem with using a 10-10-10 NPK liquid fertilizer diluted at half-strength on my oxalis plants every two weeks in spring and fall. If my plants don’t show dormancy during cool summers, I apply fertilizer once a month. However, I usually stop fertilizing during winter.
5. Maintain Moderate Humidity Levels
You don’t need to alter humidity much to get bush oxalis plants. Average room humidity (around 40% to 50%) will do, and these are achievable levels in most homes. You can use a humidifier to maintain constant levels for indoor plants.
During dry days outdoors, you can help provide optimum humidity levels by using the fine spray setting of your garden hose when watering your oxalis plants. Be sure to do this in the morning so that the moisture on the leaves has enough time to evaporate. Watering your oxalis plant overhead frequently can increase the risk of damage caused by fungal infections.
Of course, your plant’s success is only as good as what you measure, so remember to check the humidity levels as often as possible. You can use a hygrometer to get accurate readings.
6. Regularly Prune Your Oxalis Plants
Cutting back your oxalis is one of the essential steps in promoting full, vibrant foliage. Unpruned oxalis plants may become leggy and lack bountiful leaves. Pruning encourages new leaf growth and overall health, and oxalis thrives on a yearly hard prune.
Here’s how to do it:
- Remove spent flowers with sterilized shears as close to the stem base as possible.
- In late summer, the leaves will wilt and brown when the oxalis may go into dormancy. Trim back the foliage to about 1 inch (2.5 cm) from the plant base.
- Repeat the above steps in late fall or early winter if your oxalis is outdoors. Apply about 4 inches (10 cm) of organic mulch around the plant base for protection.
- If your oxalis is potted, move it to a cool, dark place for a month or two in winter with minimal watering.
7. Repot the Oxalis Plant Once Every Two to Three Years
You should repot oxalis plants every year or two for them to flourish, and occasionally swapping out planters could help you get fuller and better-looking plants. Choose a bigger pot so the plant’s roots have more room to grow and the oxalis develops better shoots.
Alternatively, you can separate the healthy bulbs or rhizomes and transplant them into smaller pots where they’ll grow rapidly and become bushy. Repotting is also an excellent opportunity to improve the growing conditions that your oxalis plants didn’t get in their old pot and soil.
Here’s how you can repot your oxalis plant:
Prepare the Pot & Soil Mix
Pick an appropriate pot depending on your purpose. I recommend choosing a pot 2 inches (5 cm) wider than the old one if you plan to repot the entire plant.
When dividing, choose a pot that’s 2-3 inches (5-7.6 cm) wider than the base of the plant. Ensure that the bulbs have at least half an inch (1.3 cm) of space between them and the walls of the pot.
When making your own potting mix, combine equal parts coco peat, loamy soil, and perlite for optimum moisture retention and drainage.
Water Before Transplanting
Ensure you properly water the plant 2-3 days before transplanting. Careful watering will help reduce the risk of transplant shock and ensure you minimize the stress on the oxalis during the process. Stress can cause your plants to lose leaves or, worse, die.
Also, moisten the new potting soil a day before transplanting. This will give the soil enough time to dry out a bit to be easier to work with while still being moist enough for the new transplant.
Check for Damage
Remove the oxalis from its previous pot and examine it for damage. Repotting is a great way to get rid of pests and ensure your plant isn’t suffering from any disease, so don’t skip this step.
Put the Plant in the Pot
First, you’ll add a little soil to the new pot and place your oxalis plant inside it. Remember to be careful, so you don’t cause any physical damage to the plant.
Then, fill the rest of the pot with soil. You don’t need to pat down or compact the soil. Compressing the soil can damage roots, remove soil oxygen, and kill beneficial organisms.
Allow the Plant to Settle in
Avoid watering the newly repotted plant until half the pot is dry. Give the plant a few days to settle down in its new home. You’ll usually notice improved results after a few weeks. Remember to care for the plant as you usually would so it grows well.
You can repot during winter—when the oxalis plants are dormant—but spring will work just as well. Remember to repot no more than once every two to three years so you don’t harm your oxalis plant.
Oxalis are hardy and beautiful plants that help beautify gardens and provide food and medicine. They’re trendy, but some gardeners struggle with getting the plants to thrive as much as they’d like.
To ensure productive growth, take care to provide:
- The correct location for sunlight
- Adequate watering
- Suitable temperature and humidity
- Regular pruning
- Repotting every 2-3 years
Although the individual tips are helpful, they’ll work even more effectively if you practice all of them when caring for your oxalis plant.