Eusideroxylon zwageri

Bornean Ironwood, or Eusideroxylon zwageri, thrives in environments with ample light, such as sunny meadows and forest edges, making it suitable for full sun and partial sun conditions. Full sun refers to areas that receive above 6 hours of sunlight per day, while partial sun areas get about 3-6 hours of sunlight. It's essential to observe how sunlight moves through your garden to ensure you choose locations that provide the right balance of light and shade, as this is crucial for the plant's health.

For Bornean Ironwood grown indoors where natural sunlight might be insufficient, especially during winter or in less sunny spaces, using artificial lights is recommended. LED lights are a popular choice as they can be customized to provide specific wavelengths needed by plants. For full sun plants, 30-50W/sq ft of artificial light is needed, partial sun plants require 20-30W/sq ft, and full shade plants need 10-20W/sq ft. The light source should be placed 12-36 inches above the plant, mimicking natural sunlight, and most plants will need 8-12 hours of light per day.

If Bornean Ironwood does not receive adequate sunlight, it may show various symptoms: new leaves growing smaller, leggy or sparse growth, faster leaf drop, slower or no new growth, and lighter-colored or yellowing leaves (chlorosis). Excessive sunlight exposure can lead to sunscald, leaf curling, wilting, and leaf scorching, where parts of the leaves appear dry, brown, and crispy.

To combat light deficiency, gradually move the plant to a sunnier location each week until it receives at least 6 hours of direct sunlight daily. Use a south-facing window and keep curtains open for maximum exposure. If the plant is large or not easily movable, consider artificial lighting, keeping it on for at least 8 hours daily. For outdoor plants, it's crucial to adapt them gradually to prevent sunburn. If sunlight is obstructed, prune branches or relocate the plant to a sunnier spot. Remember, parts of the plant affected by insufficient sunlight may not recover, but new growth will be healthy after increasing light exposure.