Oxalis triangularis: False shamrock

Family: Oxalidaceae
Common name: False shamrock, Purpleleaf false shamrock, Purple shamrock, Shamrock plant, Wood Sorrel

False shamrock leaves look beautiful whether they are awake or sleeping, the leaves folding in beautifully along the midrib like an umbrella when they close. The purple hue of their leaves make them ideal ornamental plants for your garden; or even indoors provided there is good sunlight.

These plants can grow to a height of 50 cms with long petioles that arise from the root rhizomes. They do not have an actual stem, only tuberous rhizomes and leaves arising directly from them. Leaves are made up 3 triangular leaflets that stay perpendicular to the stalk when the leaf is awake, in full sunlight.

But during the night, or during cloudy days, the leaves fold in along the central veins closing like an umbrella. This characteristic is called photonasty, the movement of a plant parts, mainly the leaves and petals in response to light.

Though it’s not very common, False shamrock plants produce beautiful, white, pink, or purple flowers that are 2-3 cms long with 5 petals. The flowers also close at night just like the leaves. Flowering happens during spring and summer, the plants going into dormancy during winter months.

False shamrock plants might droop and dry up at times, when the weather is too cold. But it can grow again from the root when ideal conditions return. This does not happen in warm, tropical weather.

It’s ok to cut back the leaves when they become old and gangly, so that new growth can happen from the rhizomes. These plants prefer well-drained, moist soil and good sunshine, without which they tend to droop and look unhealthy. Regular watering and fertilization is required for these fast-growing plants.

Leaves are eaten cooked and raw, and also used in salads. They should be eaten in moderation since the leaves contain oxalic acid crystals which can be toxic to humans and pets alike. Root tubers are also edible, and eaten raw or cooked.

There is a green variant that looks like a four-leaved clover minus one of the leaflets. Some of the popular variants are Oxalis tetraphylla or Iron cross which has green leaves with a purple center, Oxalis vulcanicola or Molten lava which has green leaves that turn orange in good sunlight, Oxalis adenophylla or Silver shamrock with silver grey leaves, and Oxalis regnellii or Triangularis with wine-colored leaves.

Propagation is through root division.