Care of a Castanospermum australe, also known as lucky bean plant or black bean, requires the following: ensuring that the potting mixture is always moist but that the roots don't sit in a pool of water; spraying the leaves regularly to prevent them from collecting dust; and providing it with bright, indirect light along with some late or early sun. Overwatering can promote the growth of fungal root rot.
The potted plant can be kept outdoors on the deck or the patio in spring and summer. It enjoys a rain shower. However, place it back indoors if the temperature goes below 50?F. The plant prefers soil that is rich in nutrients and drains easily. The soil can be a general potting soil or a mixture of lime, peat and sand with soil. Always ensure that the soil is dry before watering again. Lucky bean plants do not need fertilizers in the first year. Liquid plant food can be added monthly in spring and summer. Shaping by regular pruning and trimming controls the growth of the plant and, along with a small pot, it can form the plant into a short ornamental tree, similar to a bonsai. Always remember that the seeds and the leaves of the plant are poisonous.