About the species

Crinum thaianum from Thailand is a large bulb plant in the lily family with strap-like green leaves. The leaves reach 60–200 centimetres and eventually lie along the water surface. The plant is otherwise undemanding, but it does need plenty of room. Older specimens sometimes send up a flower stalk bearing a fragrant, elegant lily flower at the surface.

Facts

• Latin name: Crinum thaianum
• Plant type: Bulb plant
• Origin: Asia
• Height: 20–30 cm
• Growth rate: Medium
• Position: Background

Light requirement

Low light requirement. It manages with the lighting that comes with most aquariums and is happy in partial shade behind or beneath taller plants. Strong lighting does not harm it, but raises the risk of algae on the leaves because the plant cannot use all the available light.

CO₂ & nutrition

Manages entirely without added CO₂, which makes it as suitable for a simple aquarium as for an aquascape. Liquid carbon or injected CO₂ speeds up growth but is never a requirement. Dose an all-round fertiliser with iron and micronutrients every week.

Planting

Set the bulb so its top third protrudes above the substrate — a fully buried bulb rots easily. The roots work their way down by themselves. Bulb plants are solitaires and look best with open space around them.

Carefully remove the pot and rinse the rock wool off the roots before planting — leftover rock wool can otherwise hinder rooting.

Care & propagation

Cut away leaves that start to deteriorate at the base. Many bulb plants take a natural rest period where they shed their leaves — leave the bulb in place, it pushes out new shoots after a few weeks. Root tabs in the substrate make a real difference.

Position in the aquarium

Given its mature height it belongs at the back or along the sides, where it forms a dense wall of greenery and hides equipment. In a smaller aquarium it can also be used as a solitaire in one corner.

Difficulty level

🟢 Easy — grows in most aquariums without CO₂ and under ordinary lighting.

Delivery format

Delivered as a pot grown submerged, with the roots in rock wool. The pot holds several plants or stems that can be divided and planted separately.

Recommendation

A rewarding choice for large, deep aquariums where the leaves have room to spread properly. It soon covers much of the surface, so thin out the oldest leaves to let light reach the plants beneath.