Euphorbia ingens Specimen 55 / 170As this species matures it develops a thick woody texture at the base and arms, known as corking, to be able to support the extensive branching. This particular specimen has already developed large patches of corking, in a pale brown and almost orange. A classic cactus, the Euphorbia ingens is a large, green, tree like Euphorbia that can grow up to 10m tall given the right conditions, although it will take some years to do that. WATERING In Summer