What the oyster plant is
The oyster plant (Tradescantia spathacea) is a rosette-forming houseplant with stiff, sword-shaped leaves that are dark green on top and purple underneath. It is also called Moses-in-the-cradle, boat lily or Rhoeo. The names are used interchangeably; our explainer on whether Rhoeo is an indoor plant covers the naming. Unlike its cousins, the trailing wandering jew, the oyster plant forms a low, upright clump, though older plants can develop a short trunk and send out offsets.
Light, water and soil
- Light: Bright, indirect light generally gives the best colour. An east or west window is often a good spot. Harsh afternoon sun can scorch leaves, and very low light can make growth leggy and dull.
- Water: Water when the top inch or so of soil feels dry, then let excess drain away. Avoid leaving the pot in standing water. Water at the base rather than into the centre of the rosette, since trapped water may encourage rot.
- Soil: A standard, well-draining potting mix works. Adding some perlite can improve drainage.
- Pot: Use a container with drainage holes.
Temperature and humidity
Typical room temperatures suit it well. Keep it away from cold drafts, air-conditioning vents and frost (see plants near a cold window). Average household humidity is usually acceptable.
Feeding and pruning
Feed with a balanced houseplant fertiliser at a diluted strength during spring and summer, and pause in autumn and winter. Remove old, damaged or dried lower leaves as they appear. Wear gloves when pruning (see safety below).
Propagation
Oyster plants can usually be propagated from:
- Offsets (pups): Small plants that appear at the base. Separate them with some roots attached and pot them up.
- Stem cuttings: If the plant has become tall, cut off the top section with a few leaves and root it in water or moist soil.
- Seed: Possible but slower and less common indoors.
The dwarf form
Smaller, compact forms are sold as dwarf oyster plant or dwarf Rhoeo. They follow the same care as the standard form but stay more compact, which suits desks and shelves.
Common problems
- Leggy growth or faded colour: Move to brighter indirect light.
- Brown leaf tips: Can be caused by dry air, irregular watering or fertiliser build-up.
- Mushy base or yellow leaves: Often overwatering or poor drainage.
- Pests: Check for spider mites, mealybugs and scale, especially in dry rooms.
Is the oyster plant edible?
Do not eat it. Although the plant appears in some traditional uses, it is not a houseplant to treat as food, and ingestion may cause irritation or illness. Keep it out of the kitchen and away from anything edible.
Pet, child and skin safety
Oyster plant sap can irritate skin, and the plant is generally listed as mildly toxic or irritating to cats, dogs and people if chewed or swallowed. Keep it out of reach of pets and young children, wear gloves when handling or pruning, and wash your hands afterwards. If an animal or child chews it, or you see drooling, vomiting or skin or mouth irritation, contact a vet, doctor or poison helpline.
Related reading
If you enjoy the purple undersides, see our list of indoor plants with a purple underside. Calatheas have purple backs too, though they need more humidity; see the calathea care guide.
FAQ
How can oyster plants be propagated?
By separating offsets or rooting stem cuttings.
What is the dwarf Rhoeo plant?
A compact form of the same species, with shorter leaves.
Does the oyster plant need a lot of water?
It likes moderate, even watering. Let the top inch of soil dry slightly first.