Oxalis Plant Growing & Care Guide for Gardeners

Article by Dean Ravenscroft, Ph.D. - Updated 23rd Oct 2023

In this Gardener's HQ guide, we'll explore cultivating Oxalis plants in your garden, indoor spaces, and other settings.

Wood Sorrel, False Shamrock, & Sourgrass: Cultivation & Garden Use

The Oxalis genus includes the False Shamrock and Wood Sorrel.

They range in height from 5 to 30 cm (2 to 12 inches). This makes them ideal for growing in rock gardens, or close to the edges of crazy paving.

Oxalis stricta - Yellow wood sorrel by Gmayfield10.

Oxalis may flower towards the end of spring, or in the summer (species dependent). When in bloom they carry cup shaped pink or white flowers.

How to Grow Oxalis

False Shamrock, Wood Sorrel, and other Oxalis members can be grown from either roots or seeds.

If growing from roots, then bury the tubers about 4 to 5 cm (~2 inches) deep in the autumn.

The seeds should be sown using fresh seed; these are normally produced at the end of summer. Seeds of Oxalis should be lightly covered once sown.

Plants like to grow in sunny areas of the garden, and have a preference for an acidic soil (pH 4 to 7) that has good drainage.

If first growing Oxalis indoors, then the seeds will take about two to eight weeks to germinate at 12 to 21 degrees centigrade (55 - 70°F).

The young seedlings should be transplanted into the garden at about 10 cm (4 inches; small species) to 40 cm (16 inches; large varieties) apart in mid-spring, well after the last chance of a frost.

Oxalis acetosella - Common Wood-sorrel by Jörg Hempel.

Caring for Oxalis

If you require more Oxalis plants, then they can be propagated by dividing the tubers in the autumn.

They pretty much look after themselves and require no special attention when growing in the garden. They thrive in dry soils, so only water plants in exceedingly dry conditions.

Commonly Grown Oxalis Species

Oxalis triangularis

Oxalis triangularis (False shamrock), photograph by Maja Dumat; CC.

Oxalis corniculata

Oxalis corniculata (Creeping Woodsorrel / Pprocumbent Yellow Sorrel / Sleeping Beauty), picture by Andreas Rockstein; CC.

Oxalis Growing Guide and Facts

Common Names: Wood Sorrel, False Shamrock, Yellow Sorrel, Pink Sorrel, Sourgrass, Sauer klee, Culli, Shamrock, Good Luck Plant, Pickle Plant, Lemon Clover.
Scientific Names: Oxalis adenophylla; O. enneaphylla; O. lacinata; O. grandis; O. Regnellii.
Life Cycle: Hardy bulb. Hardy perennial. Half hardy perennial commonly grown as a half hardy annual by gardeners.
Height: 2 to 16 inches (5 to 40 cm).
Native: Americas, Europe, Asia, Australasia, Africa.
Growing Region: Zones 3 to 10. As a perennial in zones 6 to 10.
Flowers: Spring and/or summer.
Flower Details: Yellow, white, pink, red. Cup-shaped. Five petals. Ten stamens.
Foliage: Obovate. Usually three, sometimes four leaflets.
Sow Outside:
Seed: cover seed. Late Summer and autumn. Spacing 3 to 16 inches (8 to 40 cm).
Root: 2 inches (5cm). Autumn.
Sow Inside: Germination time: two weeks to two months. Temperature 60 to 70°F (16 to 21°C). Late summer and autumn (use fresh seeds). Transplant outdoors a few weeks after the last frost; temperatures should not drop below 41°F (5°C).
Requirements: Full sunlight or light shade. Good drainage. Soil pH 4 to 7. Ordinary soil. In cool areas bring tubers indoors over the winter. Propagate: dividing in the spring or autumn).
Family: Oxalidaceae
Miscellaneous: Invasive in many areas. Seed heads explode and can spread seed as far as 160 inches (400 cm).

Common Questions

How many members does the Oxalis genus contain?

The Oxalis genus is large, containing about 800 species. They are perhaps better known as the Wood sorrel or Shamrock genuss.

Do Oxalis members make a good garden or landscaping plant?

While some Oxalis species make lovely ornamental plants, others can be invasive and problematic. They're often appreciated for their distinctive trifoliate leaves and variety of colors.

Which Oxalis species are most frequently grown by gardeners?

Oxalis triangularis (Purple Shamrock) and Oxalis acetosella (Wood Sorrel) are commonly grown for their attractive leaves and delicate flowers.

Are Oxalis plants fragrant?

Some Oxalis species do have fragrant flowers, although the aroma is usually not strong or particularly noticeable.

What is the perfect location to grow Oxalis?

Oxalis plants generally prefer partial shade with well-drained soil. They can be grown in borders, containers, or as houseplants.

Is Oxalis invasive in the USA, if so in which states?

Some Oxalis species, like Oxalis pes-caprae (Bermuda Buttercup), can be invasive in areas like California. It's best to consult with local horticultural agencies before planting.

How do I remove Oxalis plants from my garden?

Oxalis can be challenging to remove due to their prolific bulb production. Digging up the entire plant, bulb and all, is the most effective method. Regular monitoring can help prevent re-infestation.

Summary

The Oxalis genus belongs to the Oxalidaceae family and includes a vast array of perennial and annual plants, often referred to as wood sorrels. They are known for their delicate, clover-like foliage and charming, often bright flowers.

Oxalis prefers a sunny to partially shaded location and well-drained, moderately fertile soil. The planting time depends on the species and can be in autumn or spring. Whether grown in borders, containers, or as houseplants, they offer an attractive display and make a great ground cover in suitable climates.