One of Hottest for Cacti Houseplants - Large Cactus Live Pachypodium lamerei – HuaLong

Pachypodiums are deciduous but when leaf fall has occurred photosynthesis continues through the bark tissue on the stems and branches. Pachypodiums use two methods of photosynthesis. The leaves use typical photosynthetic chemistry. In contrast, the stems use CAM, a special adaptation to harsh environmental conditions used by some plants when the risk of excessive water loss is high. Stomata (holes in plant surfaces surrounded by guard cells) are closed during the day but they open at night so carbon dioxide can be acquired and stored. During the day, carbon dioxide is released inside the plant and used in photosynthesis.
Cultivation
Pachypodium lamerei grows best in warm climates and full sun. It will not tolerate hard frosts, and will likely drop most of its leaves if exposed to even a light frost. It is easy to grow as a houseplant, if you can provide the sunlight it needs. Use a fast-draining potting mix, such as a cactus mix and pot in a container with drainage holes to prevent root rot.
This plant has gained the Royal Horticultural Society’s Award of Garden Merit.

Fertilizer, otherwise it is easy to cause fertilizer damage.