Succulents generally grow in dry and arid areas, and most are xerophytes. However, some are halophytes (growing in harsh salty environments), geophytes (underground storage organs), and occasionally they also occur as epiphytes (plants growing on other plants for their support and nutrients), like in Tillandsia.
Apart from the fleshy stems and leaves that serve as water storage organs, there are some other unique adaptations of succulents that help them to survive extremely high temperatures. Some of these adaptations are given below:
- Some plants have absent, reduced, cylindrical to spherical shaped leaves.
- The stomata present are much less in number.
- They follow CAM (Crassulacean acid metabolism) cycle to reduce the water loss and survive in dry conditions.
- Stems act as the main site of photosynthesis rather than leaves.
- The surface of the plant is generally waxy, hairy, or spiny to reduce the water loss from the surface of the plant through transpiration.
- In some species of succulents, the presence of ribs (vertical accordion-like structures found on trunks and stems) helps in reducing the area exposed to the sun by increasing the plant volume.
- The presence of thick cuticle (skin) helps in surviving the extreme temperatures by creating a physical barrier for water loss.