Euphorbia geroldii

It is endemic to northeastern Madagascar, found through the encompassing coastal forest of Iharana, in the Ambilobe region. Its natural habitat is subtropical or tropical dry forests and in the sands of coastal forests.^[3] The species is threatened by habitat degradation, fire, and clearing for charcoal production, as well as collection for both national and international horticultural trade. It is highly vulnerable to any form of disturbance, including human-induced fires.^[3] It is threatened by habitat loss. The species is on the IUCN Red List and is considered critically endangered.

A relatively fast growing species, it is cultivated as an ornamental plant and is especially popular as a thornless houseplant. Grown from cuttings, its care requirements are similar to those of other shrubby Euphorbia species from tropical regions such as Madagascar and central Africa, though it is among the easiest to grow. Hummingbirds are particularly attracted to it. Outdoors, the plant prefers semi-shade; indoors, it requires full to partial sun. Plants grown in shade should be gradually acclimated before being moved into full sunlight, as sudden exposure can cause severe scorching. This species is especially tolerant of coastal conditions and salt spray, making it an excellent choice for seaside plantings. A tall plant will need staking, otherwise it will be leggy.^[4] Pests such as mildew can occur in very humid conditions.^[3]