Hydnophytum Formicarum

The Ant Plant Guardian

What Is Hydnophytum formicarum?

Hydnophytum formicarum is a fascinating tropical plant commonly known as an “ant plant.” It is famous for its swollen base, called a caudex, which naturally forms hollow chambers where ants live in the wild.

Native to Southeast Asia, this plant grows in warm, humid forests, often attached to trees as an epiphyte. The ants protect the plant from pests, while the plant provides shelter. In cultivation, ants are not required, but the plant still develops its unique swollen structure.

It is not an aquatic plant and should never be submerged. Instead, it thrives in airy, well-draining growing media with bright indirect light.

Unusual and sculptural, Hydnophytum formicarum is perfect for collectors who enjoy rare plants with natural ecological stories.

How It Grows

This plant grows from a round, swollen caudex that becomes larger and more textured over time.

Thin green stems grow upward from the top of the caudex, producing small leaves. Growth is slow to moderate in stable, warm conditions.

The Leaves

The leaves are simple and neat.

• Color: medium to deep green

• Surface: smooth

• Shape: oval to slightly pointed

The main feature of this plant is the thick, sculptural caudex rather than the foliage.

Light Needs

Prefers bright, indirect light.

• Avoid harsh direct sunlight

• Good light supports steady growth

Low light may slow development.

Water & Growing Conditions

• Allow the growing medium to partially dry between watering

• Use very well-draining, airy mix (similar to orchid or epiphyte mix)

• Prefers moderate to high humidity

• Ideal temperature: 22–30°C

Avoid overwatering, especially around the caudex, to prevent rot.

Growing Environment

Best suited for:

• Indoor tropical plant collections

• Mounted displays

• Pots with exposed caudex

• Greenhouses

Not suitable for aquariums or submerged environments.

Care Level

Medium care.

• Suitable for growers with some experience

• Requires excellent drainage

• Slow-growing but long-lasting

Handling Note

Do not fully bury the caudex in soil. Keep part of it exposed to allow airflow and prevent rot. With stable warmth and careful watering, Hydnophytum formicarum will slowly develop a larger and more textured base over time.