Why are my leaves closing?

The plant naturally folds its leaves at night or when light levels drop.

Does it need a rest period?

Yes, it may enter dormancy once a year where you should stop watering until new growth appears.

Plant guide

Purple Shamrock.

Oxalis triangularis

Pronounced ok-SAL-iss try-ang-gyoo-LAY-riss

Also known as Wood sorrel, false shamrock, purple shamrock

false shamrock — Photo by Pavel Kacl (CC BY) via iNaturalist

This charming plant is famous for its deep purple, triangular leaves that fold up at night. It is a bulbous perennial that adds a lovely pop of color to any indoor space. You will find it quite responsive to light, as it opens and closes its foliage throughout the day.

Another photo of Purple Shamrock — Photo by Raúl A. Ruiz M. (CC BY) via gbif

At a glance

Care level: Easy
Plant type: Perennial bulb
Light: Bright indirect light is best for keeping the purple color vibrant.
Indoor light: Bright indirect
Water: Every 7 to 10 days
Mature size: 12 inches
Growth rate: Fast
Hardiness: USDA 8 to 11
Bloom time: Spring to autumn

Care

Keep the soil lightly moist but never soggy to prevent the bulbs from rotting. If the plant looks a bit tired, it might be entering a natural dormancy period where it needs less water. Watch for yellowing leaves, which often signal that the soil is staying too wet.

Watering: Water when the top inch of soil feels dry to the touch.
Feeding: Use a balanced liquid fertilizer during the active growing season.
Pruning: Trim away any spent flowers or yellowing stems to keep the plant tidy.
Repotting: Repot in the spring if the bulbs have become too crowded in the container.
Soil: Well draining potting mix
Soil pH: 6.0 to 7.0
Temperature: 15 to 27°C
Humidity: 40 to 60%
Drought tolerance: Moderate
Lifespan: Perennial, typically 5 to 10 years
Deer and rabbits: Moderate

Signs it needs repotting

Roots growing out of the drainage holes
Water running straight through the pot
Plant becoming root bound and stunted

Safety

People: The plant is mildly toxic if ingested due to high levels of soluble oxalates.
Pets: This plant is toxic to cats and dogs if ingested, as it contains soluble calcium oxalates.
Children: Keep this plant away from small children as the leaves can be a choking hazard and are toxic if eaten in volume.
Contact allergens: The sap can cause skin irritation in sensitive individuals.
Airborne allergens: There are no notable respiratory allergens associated with this plant.
Edibility: This plant contains oxalic acid and should not be consumed in large quantities.

How to identify it

Deep purple triangular leaflets
Leaves fold shut at night
Small delicate white or pink flowers
Grows from small underground bulbs

Height: 0.15 to 0.3m
Spread: 0.15 to 0.3m
Leaves: purple, maroon, deciduous
Flowers: white, light pink, 1 to 2cm

Problems to watch for

Root RotCommon
Spider MitesCommon
AphidsUncommon
Fungus GnatsUncommon
Leaf DropUncommon
MealybugsUncommon

By symptom

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Growing it

Propagation: division, corms
When to plant: spring
Overwintering: If the plant enters dormancy, move it to a cool, dark place and withhold water. Once new growth appears in spring, return it to bright light and resume regular watering.
In containers: It grows very well in pots, which is ideal for its dormancy cycle, and a 15 cm pot is usually sufficient.

Division of corms

1. Gently remove the plant from its pot during the dormant phase.
2. Separate the small corms from the main root mass.
3. Plant the corms in fresh, well draining soil.
4. Keep the soil lightly moist until new leaves emerge.

Group with other low light plants to create a lush, layered indoor display.

Grows well with

Peace Lily — They share similar light and humidity requirements.
Spider Plant — It offers a nice textural contrast to the purple foliage.

Similar species

Wood Sorrel — It is a close relative with similar growth habits.

Science

Family: Oxalidaceae
Genus: Oxalis
Order: Oxalidales
Class: Magnoliopsida
Native range: South America
Conservation: This plant is not of conservation concern.

It thrives in the dappled light of forest floors where it can easily spread through its corms.

Value to wildlife: nectar source
Pollinators: bees, butterflies
Uses: houseplant, container plant, border accent

Through the year

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Flowering

Fruiting

Foliage

Ecological indicators

Salinity: 2/9
Soil reaction: 5/9
Light: 6/9
Temperature: 7/9
Moisture: 5/9
Nutrients: 4/9

Taxonomy resolved against GBIF.

Questions people ask

Why are my leaves closing?: The plant naturally folds its leaves at night or when light levels drop.
Does it need a rest period?: Yes, it may enter dormancy once a year where you should stop watering until new growth appears.

Where the name comes from

The genus name Oxalis comes from the Greek word for sour, referring to the oxalic acid in the leaves. The species name triangularis describes the distinct triangular shape of the leaflets.

Good to know

It is commonly called the purple shamrock.
The leaves move in response to light intensity.
It grows from small, scaly corms.
It can go dormant if it gets too hot or dry.

Also in

Plants toxic to cats and dogs

Keep your purple shamrock growing

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This guide was generated with AI and checked against GBIF taxonomy. It is general information, not horticultural or veterinary advice. Read about how we build these guides.