Guide to Growing Shamrock - Oxalis
The Oxalis genus includes the Shamrock and Sorrel.
They range in height from 5 cm to 30 cm; this makes them ideal for growing in rock gardens or close to the edges of crazy of paving.
Oxalis may flower towards the end of spring or in the summer (species dependent) and carry cup shaped pink or white flowers.
Oxalis stricta - Yellow wood sorrel by Gmayfield10; creative commons.
Oxalis acetosella - Common Wood-sorrel by Jörg Hempel; creative commons.
Quick Oxalis Growing Guide and Facts
Common Names: Wood Sorrel, False Shamrock, Yellow Sorrel, Pink Sorrel, Sourgrass, Culli, Shamrock, Good Luck Plant, Pickle Plant, Lemon Clover.
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 5. Ordinary soil. In cool areas bring tubers indoors over the winter. Propagate: dividing in the spring or autumn).
Miscellaneous: Invasive in many areas. Seed heads explode and can spread seed as far as 160 inches (400 cm).
How to grow Shamrock
Shamrock, and other Oxalis members can be grown from either roots or seeds. If growing from roots then bury the tubers about 4 to 5cm deep in the autumn. The seeds should be sown using fresh seed; this normally is produced at the end of summer. The seeds of shamrock should be lightly covered once sown. Oxalis species like to grow in sunny areas of the garden and have a preference for an acidic soil (pH 4 to 5) soil that has good drainage.
If first growing shamrock indoors the seeds will take about two to eight weeks to germinate at 12 to 21 degrees centigrade. The young seedlings should be transplanted into the garden at about 10cm (small species) to 40cm (large varieties) apart in mid spring, well after the last chance of a frost.
Caring for Shamrock
If you require more shamrock plants then they can be propagated by dividing the tubers in the autumn. Shamrock pretty much look after themselves and require no special attention when growing in the garden; they thrive in dry soils, so only water them in exceedingly dry conditions.