What is the largest succulent flower in the world?
Starfish Flower - Stapelia gigantea

This is one of the most bizarre looking succulents you've even seen! Starfish Flower from Tanzania is one of the largest flowers in the plant world!
It does look like a startfish, and is absolutely beautiful! Being a succulent, the plant is very undemanding and easy to grow, doesn't need much care or water. It also doesn't mind regular irrigation, we have it in Summer Florida rains with no problem. The focal point of this plant is the fleshy, 5-pointed, star-shaped flowers (to 10-16" across), each being pale ochre-yellow with thin transverse maroon lines. It is a great container plant and very fast growing, can fill a large hanging basket within just one season. Flowers on and off during the warm season with the most profuse flowering at the end of Summer (flower buds are triggered by shortened daylight hours in fall). It is a spine-free succulent member of the milkweed (not cactus!).