Alocasia nebula 'Silver' ('Black Diamond') – Rare Metallic Alocasia from Borneo

Alocasia nebula 'Silver', also known as 'Black Diamond', is a rare tropical species admired for its metallic sheen and sculptural leaves. Originating from the limestone forests of Sarawak, Borneo, this compact collector Alocasia displays thick, bullate foliage in smoky silver shades veined in deep green to near-black. With its slow but steady growth and dramatic colour contrast, it’s one of the most striking tropical jewels for advanced plant collections.

● Natural Habitat and Origin

Native to Sarawak, Malaysia (Borneo), Alocasia nebula grows terrestrially on mineral-rich limestone slopes between 100 – 600 m elevation. It thrives under dappled light, year-round warmth of 21 – 32 °C, and humidity above 70 %. Soils are porous and slightly alkaline from limestone content. For a deeper look into the genus and its habitats, see our Alocasia Plants – Botanical Insights, Indoor Care, and Growing Tips.

● Distinctive Traits of Alocasia nebula 'Silver'

Metallic foliage: Thick, corrugated leaves shimmering in silver-gray tones with bold dark venation.
Leaf reverses: Subtle plum-purple undersides add depth and contrast.
Growth form: Compact rosette habit reaching 30 – 40 cm indoors.
Durability: Slow-growing but resilient when kept warm and humid.
Toxicity: Contains calcium oxalate crystals; keep away from pets and children.

● Alocasia nebula 'Silver' Care Guide

Light
Bright, filtered light is ideal; too much sun can dull the metallic surface. Moderate shade tolerance allows flexible placement. For window direction advice, visit our window orientation guide.
Watering
Water when the top 10 – 15 % of substrate is dry. Keep evenly moist but never saturated. For accurate watering practices, refer to our Ultimate Guide to Watering Houseplants.
Humidity
Maintain 70 – 80 % humidity for strong foliage. Grouping plants or using enclosed setups stabilises moisture levels. Learn more in our Misting – Pros and Cons article.
Temperature
Best kept between 21 – 28 °C. Avoid dips below 18 °C or abrupt drafts. Consistent warmth ensures steady leaf production.
Soil
Use a porous, mineral-infused mix of coconut coir, bark, perlite, and crushed charcoal. A small amount of dolomite supports its limestone adaptation (target pH 6.5 – 7.0). For structure tips, read our Best Aroid Substrate & Root-Matched Mixes.
Feeding
Apply a diluted balanced fertiliser every 4 – 6 weeks during active growth. Flush the mix occasionally to prevent salt buildup.
Repotting
Repot every two years or when roots crowd the pot. Use shallow containers with drainage suited to rhizomatous roots.
Propagation
Divide rhizomes or sprout basal corms in warmth and humidity. Each piece must have a viable node and roots for success.
Semi-Hydro Substrates
Adapts well to mineral or semi-hydro setups using pumice or clay aggregate. Keep water levels low for oxygen exchange.

● Common Problems & Remedies

Yellowing leaves: Usually from excess moisture; allow partial drying between waterings.
Brown edges: Low humidity or fertiliser residue—raise humidity and flush substrate.
Drooping foliage: Reaction to temperature stress or recent transplanting; stabilise conditions.
Pests: Inspect regularly for mites or thrips. Prevention methods in our Pest Control Articles.
Root rot: Ensure drainage and airy substrate; repot if roots appear dark or soft.

● Extra Growing Tips for Alocasia nebula 'Silver'

Rotate occasionally for even light exposure and symmetrical growth.
Clean leaves gently to maintain their metallic gloss.
Provide filtered water to avoid mineral spotting.
Support larger leaves with discreet stakes if necessary.

● Etymology & Botanical Background

The species name nebula comes from the Latin “mist” or “cloud,” describing its ethereal silver foliage. Described in 1999 by A. Hay, it remains among the most distinctive Bornean Alocasia species, prized for its thick, bullate texture and compact form.

● FAQs – Alocasia nebula 'Silver'

How large does it grow indoors? Usually 30 – 40 cm tall under steady warmth and humidity.
Can it handle low light? Survives in medium light but thrives in bright, filtered exposure.
Is it pet-safe? No – contains calcium oxalate crystals and is toxic if ingested.
What soil pH suits it best? Neutral to slightly acidic (6.5 – 7.0) replicates its limestone habitat.

● Bring Home Alocasia nebula 'Silver'

Bring home Alocasia nebula 'Silver' and experience its rare metallic sheen and sculptural texture. A compact tropical collector plant that brings Borneo’s exotic elegance into any modern interior.