Cyrtosperma Johnstonii ‘Black Jack’-Rare

Description & Care

Cyrtosperma johnstonii ‘Black Jack’ is a bold, architectural aroid prized for its massive, arrow-shaped leaves in deep, near-black green tones with striking, high-contrast veining. Its dramatic size, glossy texture, and powerful upright presence make it a true statement plant and an instant focal point in any collection. While it is often sold in the plant trade as “Alocasia Black Jack” due to its similar appearance and care needs, this plant is botanically a Cyrtosperma, a closely related but distinct genus within the aroid family.

Like its Alocasia cousins, Cyrtosperma ‘Black Jack’ thrives in warm, humid conditions and appreciates consistent moisture and bright, indirect light. It grows from thick, robust rhizomes and can become an impressively large, commanding plant over time. During cooler or lower-light periods, it may rest between growth cycles, then return with even larger, more dramatic leaves.

Light: Bright, indirect light. Avoid direct sun, which can scorch the leaves.

Water: Keep soil evenly moist but not soggy. Do not allow to fully dry out. Prefers a well-draining, airy aroid mix.

Humidity: Prefers higher humidity; thrives at 60%+ and benefits from a humidifier or cabinet environment.

Temperature: 65–85°F. Keep away from cold drafts and sudden temperature changes.

Growth: Moderate to fast grower with large, upright, dramatic dark foliage. Grows from thick rhizomes and can become quite large over time. May go semi-dormant in cooler conditions.

Flowers: Rare and insignificant; grown primarily for its foliage.

Care Level: Moderate.

Exact plant shown will be shipped.

Internal Use Only: A27