Alocasia macrorrhiza ‘Black Stem’
 
Common Names Black Stem Elephant Ear, Giant Taro ‘Nigra’, Alocasia plumbea ‘Nigra’
 
Zones 9B–11
 
Alocasia macrorrhiza ‘Black Stem’ is a dramatic cultivar distinguished by its deep charcoal-black petioles and bold, upright foliage. Native to Southeast Asia and Eastern Australia, this variant adds architectural intensity to tropical gardens and interiorscapes. Its thick, rigid stems and sculpted forest-green leaves create a striking silhouette, especially when backlit. The dark pigmentation is due to high anthocyanin concentration, extending subtly into the leaf veins for added contrast.
 
Key Features
Growth Habit: Upright, architectural; moderate to fast growth
Height: 4–6 ft. tall; 3–4 ft. wide
Trunk: Herbaceous; corm-based growth
Leaves: Arrow-shaped to heart-shaped; glossy, textured green with dark veins; 18–30 in. long
Petiole: Thick, black to deep purple; rigid and upright
Inflorescence: Rare in cultivation; creamy-white spathe with pale spadix
Fruit: Not typically produced in container culture
Ecology: Cultivar of A. macrorrhiza or A. plumbea; selected for petiole pigmentation and leaf texture
 
Growing Conditions
Light: Bright indirect light to partial shade; tolerates filtered morning sun
Watering: Keep soil consistently moist but not soggy; reduce in winter
Soil: Rich, well-draining mix; ideal blend includes potting soil, orchid bark, perlite, and coco coir
Temperature: 65–85°F (18–29°C); protect from cold drafts and frost
Humidity: High (60–80%); misting or pebble trays recommended indoors
Propagation: By division of corms or offsets
Tolerance: Sensitive to overwatering and low humidity; not drought-tolerant
 
Landscape Use Perfect for bold tropical compositions, shaded patios, and moody interiorscapes. Pairs well with Philodendron ‘Dark Lord’, Colocasia ‘Black Magic’, and Calathea ‘Dottie’ for layered dark foliage themes.