Oxalis triangularis 'Purple Shamrock' is one of several Oxalis cultivars. There are ornamental varieties like the striped 'Candy Cane' and the green-leaved, white-flowered Oxalis regnellii which is also called Lucky Shamrock.
Other varieties are known for their herbal uses. Oxalis tuberosa is valued for its tubers which are sold in South American fruit markets. The raw tubers have a lemon flavor when they are first harvested. They can be dried in the sun and will become sweet as figs. The fresh and dried roots are both tasty when baked or boiled.
*The young leaves and flowers of Oxalis tuberosa are edible but contain high amounts of oxalic acid and so should be consumed sparingly and with caution.
, or yellow woodsorrel, is green with tiny yellow blooms. The leaves taste like sour lemon and can be boiled to make a lemonade-like drink. The seed pods look like little bananas and will burst when ripe, launching seeds out in every direction.
They sprout eagerly so cultivate this plant at your own risk. Many gardeners consider Oxalis stricta to be a noxious weed.
is also green, with white flowers. Redwood sorrel is not as weedy as Yellow woodsorrel and many gardeners like to use it as a groundcover. It is shallow rooted and easy to pull up if you change your mind.
Oxalis oregana prefers shade (its leaves fold when the sun shines directly on them).
Oxalis triangularis 'Purple Shamrock' is one of the prettiest ornamental varieties. The leaves are large and purple--darker toward the edges, more vibrant in the centers.
Each of the three segments is the shape of a triangle.
The pale pink flowers are also larger than those of the medicinal types and they are held higher above the foliage. The blossoms seem to be jumping up saying, "look at me"!
The plant grows to a height of less than one foot making it a perfect container plant, ground cover, or under planting for taller plants.
This burgundy Oxalis triangularis plant spends the summer next to a Christmas cactus on my Aunt Charlotte's front porch in Connecticut.
Both plants spend the winter in her garden window.
Plant the bulbs 1 inch deep in well-draining soil.
They will not tolerate water logging.
If you are planting them in a pot, an 8 inch size will hold 5 bulbs. It doesn't matter which way the roots are positioned in the soil.
A spot in bright shade or part sun is best. The brighter the light, the more intense the color of the leaves.
The roots will produce foliage in 6 weeks and flowers within 10.
Leave the leaves in place until they yellow and die back. Once this happens, you can safely remove them as the bulbs will be dormant. Oxalis triangularis 'Purple Shamrock' is hardy in the ground in zones 6-10.
*Oxalic acid can aggravate conditions such as arthritis, gout, and kidney stones