Oxalis

( OX - al - iss )

At-A-Glance Information

This genus of flowering perennials needs light shade in warmer climates and regular water. These plants are commonly called Wood Sorrel, Yellow Sorrel, Pink Sorrel, False Shamrock, and Sourgrass. The leaves resemble Clover leaves, and flowers can come in pink, white, rose, or yellow. Many species are considered invasive in open areas. Use these plants to fill between stepping stones, add to containers or mixed beds, or as small-space groundcover plants. Take care when planting these in the garden, as all plant parts from most species are toxic to humans and pets.

Oxalis Species and Varietals

The genus Oxalis is a member of the plant family Oxalidaceae and includes 550 species. The genus name is derived from the Greek word 'oxys' which means sharp or sour, referring to the oxalic acid content of the plants which give them a sour flavor. The best growing zones for Oxalis vary depending on the species. For more information, see the descriptions below. To find your zone, click here: Zone Map.

Oxalis acetosella (Wood Sorrel, Shamrock, Stabwort)
This species grows best in zones 1-10 and 14-24; it is native to many northern temperate regions of the globe. It reaches 5 inches tall and spreads via rhizomes. Blooms appear in late springtime and are white with purple to pink veins. It can be somewhat invasive in woodland areas.

Oxalis adenophylla (Silver Shamrock, Chilean Oxalis)
This species is best in zones 4-9 and 12-24, and is native to South America. It has a dense, compact habit reaching 4 inches tall and 6 inches wide. Each leaf has many grey-green leaflets. Flowers are lilac-pink and have deeper pink veins, blooming in late spring on 4-6 inch tall stems. These are great candidates for rock gardens and can also be grown in pots or in the ground. It needs great drainage, and should be planted in fall.

Oxalis alpina (Alpine Woodsorrel)
​These plants are native to North and Central America. The specific epithet alpinus refers to the species' habitat range in alpine environments.

Oxalis articulata (Pink Sorrel, Pink Wood Sorrel, Windowbox Wood Sorrel, Chari Amilo, Sourgrass, Netho (Khatta) Saag)
These perennial flowering plants are native to temperate regions of South America, and have been introduced to and naturalized in many other areas of the world. These plants typically produce pink to violet flowers and reach 18 inches tall.

Oxalis bowiei (Bowie's Wood Sorrel, Red-Flower Wood Sorrel, Cape Shamrock)
These plants are native to South Africa, and have naturalized in Australia. The species is named for Kew plant collector and botanist James Bowie, and produces flowering stems that exceed a foot in height. They produce flowers for a long blooming season during the summer months.

Oxalis corniculata (Creeping Woodsorrel, Procumbent Yellow Sorrel, Sleeping Beauty)
These small, creeping plants grow well in moist climates, and are native to southeastern Asia. Leaves are green, turning maroon with exposure to sun. Flowers are small and yellow, closing when not in direct sun (hence the common name 'Sleeping Beauty').

Oxalis dillenii (Southern Wood-Sorrel, Slender Yellow Woodsorrel, Dillen's Oxalis)
Often considered a weed, this species is native to North America. Plants are low-growing, like many others in the genus, and produce green foliage and tiny yellow flowers. 

Oxalis grandis (Great Yellow Woodsorrel, Large Yellow Woodsorrel)
These annual plants are native to the eastern United States, and bloom from May through June. Flowers are yellow and foliage is green. Leaves are somewhat larger in this species than those of others in the genus. These plants prefer to grow in sandy woods and alluvial soils.

Oxalis hedysaroides (Fire Fern)
These plants are native to Colombia and Ecuador, and produce golden-yellow flowers. Leaves turn dark purple to reddish with sun exposure and close up at night. These plants typically reach about 12 inches tall with a 4 inch spread, and have a trailing habit.

Oxalis hirta (Hairy Sorrel)
This species of Oxalis grows best in zones 8, 9 and 14-24, and is native to South Africa. Reaches a foot tall and a foot and ahalf wide. It has an upright, branching habit that droops somewhat under the weight of the foliage and flowers. Leaves are small and pale green, and flowers are pink, blooming in late fall and winter. Plant goes dormant in summer. To plant, space 3-5 inches apart and and an inch deep. This species is a great candidate for rock gardens.

Oxalis lasiandra (Palm Tree Oxalis, Mexican Shamrock)
This species is best in zones 8, 9, 12-24, H1 and H2 and is native to Mexico. This plant has a taproot and forms a clump of foliage that reaches 16 inches tall and wide. Plants produce reddish leaf stems and green leaves. Flowers are dark red to pink-magenta and bloom summer through fall.

Oxalis montana (Mountain Woodsorrel, Wood Shamrock, Sours, White Woodsorrel)
These plants are perennials and are native to North America's eastern regions. Foliage is green, and flowers are white with pink central bands. Plants typically reach about 4 inches tall at maturity and have a 6-inch wide spread.

Oxalis oregana (Redwood Sorrel, Oregon Oxalis)
This species grows well in zones 4-9 and 14-24, and is native to the forests on the coasts of Washington, Oregon, and California. It reaches 10 inches tall and spreads by rhizomes. It blooms in spring and fall, with flowers in white or pink with lavender veining. It makes an attractive shady area groundcover and will choke out other plants nearby. It is considered somewhat invasive, especially in favorable conditions. It can tolerate wet conditions, but will die back in cooler temperatures.

Oxalis pes-caprae (African Wood-Sorrel, Bermuda Buttercup, Buttercup Oxalis, English Weed, Goat's-Foot, Soursob, Soursop, Suring, Hommayda)
These plants produce yellow flowers and green foliage. They are considered a noxious weed in many areas of the world, including California, Europe, the Middle East, and Australia. It is notoriously hard to eliminate once it has spread.

Oxalis purpurea (Oxalis variabilis) (Purple Woodsorrel)
This species is best in zones 8, 9 and 12-24. It is native to South Africa, and reaches 4 inches tall and 6 inches wide. Leaves are dark green and flowers are rosey-red, blooming in fall and winter. It spreads by both bulbs and rhizomatous roots but is not aggressive or considered invasive. Plant bulbs an inch deep and 3-5 inches apart. Variety 'Grand Duchess' has larger flowers i rose-pink, white and lavender.

Oxalis stricta (Common Yellow Woodsorrel, Common Yellow Oxalis, Upright Yellow-Sorrel, Lemon Clover, Sourgrass, Juicy Fruit, Sheep Weed)
These plants are native to North America and Eurasia. It has naturalized on most continents around the world. Flowers are yellow and foliage is green. Plants typically reach up to nine inches tall when mature and in bloom, though they can also be much shorter, depending on the climate.

​Oxalis spiralis vulcanicola (Spiral Sorrel)
This sub-species grows best in zones 8, 9 and 12-24, and its varieties are more well-known, and more widely grown, than the species. Varieties include 'Zinfandel' (,to 10 inches tall with black-purple foliage) and 'Molten Lava' (pictured, with green to orange leaves and yellow flowers).

Oxalis tetraphylla (Oxalis deppei) (Lucky Clover, Four-Leaf Sorrel, Four-Leaf Pink Sorrel)
This species reaches 6-10 inches tall and forms a clump that spreads slowly by tubers. Leaves are medium green and are banded with purple at the base. Flowers are bright pink and bloom in spring through summer. This plant needs well draining soil and is great in containers. It grows best in zones 7-9 and 12-24 and is native to Mexico.

Oxalis triangularis papilionacea 'Atropurpurea' (Oxalis regnelliii trianglaris) (Purple Shamrock, False Shamrock)
This species grows best in zones 7-9 and 12-24 and is native to South America. It reaches 12 inches tall and 18-24 inches wide, and forms a mound of burgundy foliage. Flowers are light pink. This plant is wonderful for containers and is not invasive.

Oxalis tuberosa (Uqa, Oca, Yam)
These plants, native to the Andes, are crop competitors to the potato. There are many cultivars and varietals. These plants are cultivated as crops in many areas of the world, including Bolivia, New Zealand, Peru, Venezuela, Colombia, France, and Mexico.

​Oxalis versicolor (Candy Cane Sorrel)
​This species is best in zones 6-9 and 14-24; it is native to South Africa. It reaches 3-6 inches tall (12 inches at the maximum) and 8 inches wide. Leaves are medium green, and flowers are white and funnel-shaped. Petals have a crimson coloring on the backsides. Bulbs should be planted in fall for springtime blooms, set 1 inch deep and 3-5 inches apart. Hardy to 23 degrees Fahrenheit.

Caring for Oxalis

Propagation

Problems and Pests

Gallery

Camellias are great candidates to be grown as container plants on your patio.
A field of thea sinensis
Camellia hiemalis 'Shishi Gashira'

Videos

A video all about growing camellias successfully
Propagating camellias

Resources

Wikipedia: Oxalis
The New Sunset Western Garden Book: The Ultimate Gardening Guide (2012) - Pages 467 - 468, Oxalis 
If you have any questions, comments, concerns, or photos you’d like to add to the gallery, please let me know by sending me a message using the button below!
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