🌵 Cacti are well known for their spines… 🌵
and the spines have two main benefits for the cacti. They make the plants more difficult to eat, increasing their chances of survival. They can also shield the plant against the strong sunlight they experience in the wild, preventing sunburn.
Cactus spines grow out of a part of the plant called the areole. Although other plants might have sharp defences like thorns and prickles, areoles are unique to cacti – no other plants have them!
Areoles are raised areas on the body of the cactus. They can be fluffy, hairy or velvety. Not every cactus will have spines but when they do, they always grow out of the areole. Young spines are softer and harden up as they age.
Larger spines often point straight out of the centre, called central spines, and the ones that point in other directions are called radial spines. Areoles aren’t all about spines though – flowers develop here too and eventually fruit if the flower is pollinated.
Cactus growers often select their plants for the beauty of their spines. They are very varied, coming in all sorts of shapes and sizes.