The crossword solution for the term 'Plant of Rock' is Robert, which is a 6 letter word. Robert is a common name, but it can also refer to a specific type of plant. Robert is a type of succulent that grows in rocky areas and is known for its ability to survive in harsh conditions. It is a low-growing, evergreen shrub with thick, fleshy leaves and small white flowers. Robert is native to South Africa and is often used as an ornamental plant in gardens.