Hoya callistophylla 'Black cat' (IML 3576)

Hoya callistophylla IML 3576 ‘Black Cat’ – rare climber with bold veining

Hoya callistophylla IML 3576 ‘Black Cat’ is a rare and highly desirable clone celebrated for bold, dark-green leaves with deep, embossed veins and clusters of sweetly scented, star-shaped flowers. Originating from the humid lowland forests of Sabah, Borneo, this vigorous climbing species thrives indoors with steady warmth, bright light, and patient care. For collectors seeking both foliage drama and reliable flowering, ‘Black Cat’ is a true standout.

What makes Hoya callistophylla ‘Black Cat’ unique

• Distinctive veining: Broad, leathery leaves with striking dark, recessed veins that intensify with age.
• Vigorous climber: Rapid-growing, semi-woody vines ideal for moss poles, trellises, or hanging baskets.
• Scented umbels: Clusters of pale yellow to greenish blooms releasing a gentle, sweet fragrance.
• Adaptable indoors: Handles typical indoor humidity and bright, filtered light with ease.

Essential facts about Hoya callistophylla ‘Black Cat’

• Origin: Lowland forests of Sabah, Borneo.
• Growth form: Epiphytic climber with trailing or twining vines.
• Leaf size: Mature leaves can exceed 20 cm under ideal conditions.
• Toxicity: Generally considered non-toxic to humans; milky latex may irritate skin or sensitive pets if ingested or chewed.

Care guide for Hoya callistophylla ‘Black Cat’

• Light: Prefers bright, indirect light; avoid harsh midday sun that can scorch foliage.
• Water: Let the top 2–3 cm of substrate dry before watering again. Overwatering is the most common cause of root issues.
• Humidity: Ideal above 60 %, but tolerates down to about 45 % if airflow is good.
• Temperature: Best between 18–28 °C; protect from cold drafts and sudden drops.
• Substrate: Loose, airy mix such as orchid bark, perlite, coco coir, and a small portion of compost or humus.
• Fertiliser: Use a balanced liquid fertiliser at half strength every 4–6 weeks during active growth.
• Propagation: Stem cuttings root easily in water, perlite, or sphagnum moss under warm, humid conditions.
• Pruning: Trim long vines to shape and encourage branching; avoid cutting peduncles, as blooms arise from older spurs.

Troubleshooting tips for Hoya callistophylla ‘Black Cat’

• Yellowing leaves: Most often caused by excess watering – let the mix dry further and check drainage.
• Curling or speckled leaves: Inspect for spider mites or mealybugs and adjust humidity and airflow.
• No flowers yet: Keep the plant slightly root-bound and provide consistent bright light; flowering increases with maturity.

Extra growing advice for Hoya callistophylla ‘Black Cat’

To echo its native habitat, give Hoya callistophylla ‘Black Cat’ stable warmth, bright filtered light, and time to fill its pot before repotting. Flowering improves as the plant matures, so avoid frequent disturbances or unnecessary pruning. With patient, consistent care, ‘Black Cat’ develops into a statement plant that rewards you with lush veined foliage and sweetly perfumed umbels.

Botanical background and etymology of Hoya callistophylla ‘Black Cat’

Hoya callistophylla was first described by T. Green in Fraterna 13(4): 2 (2000) and belongs to the family Apocynaceae. The name comes from Greek: kallos (“beautiful”) and phylla (“leaf”), directly referencing its striking foliage.

Clone IML 3576 was collected in Sabah, Borneo, by David Liddle and is distinguished by darker pigmentation and more dramatic venation compared to typical forms. The name ‘Black Cat’ is an informal collector’s name for this particularly dark-veined clone.

Add Hoya callistophylla ‘Black Cat’ to your collection

If you are looking for a striking, fast-growing Hoya with rich colour and texture, Hoya callistophylla IML 3576 ‘Black Cat’ is an excellent choice. Bring a touch of Sabah’s rainforest elegance into your home and enjoy the combination of bold veined foliage and sweet, starry blooms for years to come.