Alocasia macrorrhizos 'Borneo Giant'
Botanical Name — Alocasia macrorrhizos ‘Borneo Giant’
Common Name — Elephant ear
Plant Family — Araceae
Alocasia plants have a broad native range. They grow indigenously in tropical rainforests, along streams and marshes in India, Southeast Asia and Southern China, through the South Pacific Islands to Eastern Australia. Specimens can grow up to 15’ tall with leaves growing 3’ wide by 4’ long.
- Alocasia plants enjoy bright, indirect light. Avoid direct sun. This can burn the leaves.
- This plant prefers warm temperatures, between 60 and 80 ºF is ideal. Alocasias will go dormant in temperatures below 60 ºF.
- As a tropical plant Alocasia ‘Borneo Black’ prefers high humidity but will tolerate lower levels. To improve humidity use humidifiers or group plants together to create a greenhouse effect.
- Water your Alocasia’s soil enough to keep it consistently moist but not soggy. This plant is particularly sensitive to root rot and will not tolerate overly moist soil.
- Plant your Alocasia in moist, nutrient-rich, well-draining soil. These plants prefer a loose mix. Add pumice to improve drainage, and coco coir to improve water retention for these moisture loving plants.
- Alocasia ‘Borneo Giant’ inflorescence features a green spadix sheathed in a white spathe.
- Blooms occur during the spring and summer months, though this plant rarely flowers indoors.
- These plants prefer nutrient rich soil, and will appreciate a boost during the growing season. Fertilize your Alocasia every two weeks with a balanced fertilizer, spring through fall.
- Propagate Alocasia plants by division. Use clean, sharp shears to divide the plant into smaller pieces, making sure each piece has a few corms attached.
- These plants can also be propagated by separating tubers. Gently uproot the plant, and divide the tuber from the parent plant. Plant it in soil, making sure the top of the tuber meets the soil surface. Keep soil warm and moist and provide plenty of humidity to encourage growth.
- Alocasia plants are not particularly susceptible pests though it is always a good idea to keep an eye out for common pests such as spider mites and aphids.
- These plants are more susceptible to bacterial and fungal infections. Keep an eye out for crown, stem, and root rot. Overwatering can increase the chances of these types of infections. Leaf spot disease is another concern. Avoid getting water directly onto the leaves.
Maintenance (pruning, legginess, repotting)
- Prune away any unhealthy leaves. If your Alocasia is potted outside and hit by a cold snap, prune yellow leaves back to the base of the plant.
- Sometimes all of the leaves will be damaged. In this case, cut back the entire plant to its base, the crown of the plant will regenerate slowly.
- Extremely toxic to pets. This plant contains calcium oxalate crystals that cause swelling of the mouth, tongue, and upper respiratory. Keep out of reach of children and pets.
- Speak to a doctor or veterinarian immediately if ingested. Severe cases of poisoning can be fatal.