The "Kadak Bijli" Oyster plant, also known as Tradescantia spathacea, is a perennial herb with a rosette growth habit. It is characterized by its fleshy, lance-shaped leaves that are dark green on top and purple underneath. The plant produces small white flowers nestled within boat-shaped, purple bracts, giving it the common name "Moses-in-the-Cradle" or "Boat Lily". 

Here's a more detailed description:

Appearance:

Foliage:

The plant forms a rosette of waxy, lanceolate (spear-shaped) leaves. 

Leaf Color:

The upper surface is typically dark green, while the underside is a striking purple, often described as glossy or vivid violet. Some varieties, like 'vittata', have yellow stripes on the upper surface. 

Flowers:

The small, white flowers are clustered together and emerge from within the boat-shaped, purple bracts. 

Size:

It's a relatively small plant, with rosettes typically reaching 12-16 inches across. The leaves can grow to be about 12 inches long and 3 inches wide. 

Growth Habit:

It's an erect, perennial herb that forms clumps or colonies. It tends to grow upwards rather than spreading out, making it suitable for containers but not ideal for hanging baskets. 

Other Names:

Tradescantia spathacea

Rhoeo spathacea: (formerly used in horticulture)

Moses-in-the-Cradle

Boat Lily 

Growing Conditions:

Light: Prefers bright, indirect light.

Soil: Well-draining soil is important.

Watering: Avoid overwatering, as it can lead to root rot.

Climate: Hardy in USDA zones 9-12. Can be grown indoors in colder climates.

Propagation: Easily propagated from cuttings or division. 

Additional Notes:

The sap can cause skin irritation for some individuals.

The plant is considered toxic to pets.

It can become weedy in some regions and naturalize easily.