Euphorbia Pentagona, aka Pincushioneuphorbia, is considered an easy-care plant and has a good tolerance to both drought and heat which makes it a favourite among plant parents. This pentagonal prism-shaped cactus is native to South Africa, and has spines red in colour when young and eventually age to a grey colour. As it grows, new branches can grow from the sides, often appearing where spines once were, which makes a fascinating architectural addition to any room.