Creeping woodsorrel (Oxalis corniculata) is a flowering herb which grows aggressively. The leaves have a lemony flavor and are often made into tea that’s rich in vitamin C. However, if ingested in large amounts the oxalic acid for which the genus is named can begin to block the body’s calcium absorption.
I. Appearance and CharacteristicsÂ
Oxalis corniculata, the creeping woodsorrel, procumbent yellow sorrel or sleeping beauty, is a somewhat delicate-appearing, low-growing herbaceous plant in the family Oxalidaceae.
It is a small creeping type of wood sorrel that tends to grow well in moist climates. It resembles the common yellow woodsorrel, Oxalis stricta.
This species probably comes from southeastern Asia. It was first described by Linnaeus in 1753 using specimens from Italy, and it seems to have been introduced to Italy from the east before 1500. It is now cosmopolitan in its distribution and is often regarded as a weed in gardens, agricultural fields, and lawns.
It has a narrow, creeping stem that readily roots at the nodes. The trifoliate leaves are subdivided into three rounded leaflets and resemble a clover in shape. Some varieties have green leaves, while others, like Oxalis corniculata var. atropurpurea, have purple. The leaves have inconspicuous stipules at the base of each petiole. The flowers are small and yellow, with some having round-edged petals and others possessing sharp ends. The flowers close when direct sun is not hitting the plant, hence the name “sleeping beauty”. Some specimens can have a single flower while others can have over 20.
The fruit is a narrow, cylindrical capsule, 1–2 cm (0.4–0.8 in) long, and noteworthy for its explosive discharge of the contained seeds, 1 mm (0.04 in) long. Pollen is about 34 microns in diameter.
II. How to Grow and Care
Sunlight
Creeping woodsorrel needs medium bright sunlight and should be kept away from the direct bright sun. They enjoy the morning light, so a window facing the rising sun would be a perfect spot as the glass will filter most of the harmful light and it will be protected from the intense midday sun. For perfect results, you can even rotate your plant so the flowers would follow the moving sun every couple of weeks. If grown in a garden, partial shade is recommended. Keep in mind that creeping woodsorrel has a lot of species and cultivars and you should consider the exposure to the sun when choosing your creeping woodsorrel species.
Temperature
In tropical and temperate regions, creeping woodsorrel can be quite resilient little plants, even though they are native to South Africa and Brazil. The indoor temperature is quite suited for them, so their optimum is between 16 to 21 ℃. They require moisture, but not excessive so they should be watered every 2-3 days, ideally when the topsoil dries out. If you are growing creeping woodsorrel in your garden, water them daily only during prolonged droughts or if there is little rainfall in your area.
Watering
Creeping woodsorrel has medium water requirements, but remember that its bulb does not require sogginess. Water when the top inch of soil is dry and be sure to allow the soil to dry between the waterings. Always ensure that the top 5 cm of the soil is moist after every watering. Rainwater is perfect, but tapwater will work just fine, provided it’s not too hard or too cold.
Soil
Creeping woodsorrel can be sensitive to overwatering as soggy soil can promote the bulb root rot. This means that you should check for drainage in your garden before you choose your planting site and if you plan on growing them potted indoors, make sure that your container can be drained from the excess of water. Creeping woodsorrel requires neutral to slightly acidic soil (pH 6.0-6.5). Regarding the soil type, creeping woodsorrel is not too specific, so a well-drained, store-bought potting mix will work just fine.
Fertilizing
Creeping woodsorrel is a light feeder and does not require much additional feeding if grown in balanced soil. A balanced, all-purpose liquid fertilizer (half strength) once every couple of months will work just as well as slow-release fertilizer pellets. You should not add any additional nourishment when the plant is in its winter dormancy period. Additionally, when repotting, mix in some organic compost with the soil to give it some extra boost in its sprouting period.
Planting Instructions
Creeping woodsorrel generally blooms in the summer, so it should be planted during springtime, especially if planted in the garden. As creeping woodsorrel requires proper drainage, choose locations in your garden in which the rainwater does not pool. Also, take into consideration the different sunlight requirements according to the creeping woodsorrel species that you plan to plant in your garden. It is smart to plant bulbs and not from the seed, as you are never sure if all seeds will germinate.
Loosen the soil and place the bulbs down about 4 cm and do not worry about on which side you place the bulb, as they will always grow upwards. Creeping woodsorrel looks stunning and grow well in groups, but be sure to make a bit of space between the bulbs (8 to 10 cm). If grown in pots, place up to 8 bulbs in a 15 cm container, up to 14 bulbs in an 20 cm pot and up to 20 bulbs in a 25 cm pot. Mix in some compost with the extracted soil, return the soil around the bulb and water generously at the end so the soil settles well. They should start sprouting after a couple of weeks.
Pruning
Creeping woodsorrel requires pruning only when entering their winter dormancy. When the foliage starts to wither, this is the sign that your creeping woodsorrel is entering its dormant phase. After the leaves turn brown, just remove the dead foliage and don’t worry, this is normal and they will return in the next growing season, which could start anywhere from 2 to 4 weeks. Remember to always disinfect your pruning tools because this minimizes any chances of cross-contamination.
Propagation
The best time for creeping woodsorrel propagation is during wintertime when the plant is dormant. This is easily done by separating the bulb (or tuber) to create additional plants. Just remove creeping woodsorrel from the pot and gently pull the bulbs apart. You can do this by hand. Once separated, just place the bulbs into new containers.
Transplanting
The optimal window for transplanting creeping woodsorrel is between late spring and early summer (S3-S4), as the plant can acclimatize better with the consistent temperature. Creeping woodsorrel thrives well in light shade or full sun, with fertile, well-drained soil. Remember, while transplanting, minimize root disturbance to avoid plant shock.
Overwintering
Creeping woodsorrel usually goes through the winter dormancy phase, in which everything that grows above the soil level withers and dies off. This can also happen if the plant is not properly taken care of. During this time, do not add any fertilizer and drastically reduce the watering regime. After several weeks, when you notice that the sprouting has started, begin light watering. When you notice that the plant is it’s a full sprout, resume normal watering regime.
III. Uses and BenefitsÂ
- Ornamental uses
Creeping woodsorrel is a great addition to woodland or wildlife gardens, although care should be taken to make sure it does not crowd out other plants. It is also possible to grow this pretty plant in containers for courtyards. It is summer flowering, attracting a variety of pollinating insects.
- Medicinal uses
Indigenous peoples of Taiwan frequently grow this plant (known roughly as p-r-səʔ) as a cure for snake bites and scabies.
- Culinary uses
The leaves of woodsorrel are edible, and have a tangy taste like lemons. A drink can be made by infusing the leaves in hot water for about 10 minutes, sweetening, and then chilling. The entire plant is rich in vitamin C. Any wood sorrel is safe in low dosages, but if eaten in large quantities over a length of time can inhibit calcium absorption by the body.
