Pachypodium Species, Horombe Clubfoot, Yellow Bell Pachypodium

For the second time my horombense has become hollow feeling through the base, I somehow got it to firm up once before but I’m concerned...Read More it may be in worse shape this time.any help on understanding this would be greatly appreciated. I am in Palm Springs, and I water these frequently in the summer, I have also used shade cloth to filter the sunlight as this summer has been brutal on almost all plants exposed to it.
Thanks

My 1st attempt at raising a succulent from seed. The little spines are my favourite part of what is becoming my favourite plant, despite ...Read Moreit also being the tiniest of them all. After coming within centimetres of disaster courtesy of the local paper boy, it went into the greenhouse. My photo could have been a lot better so I'll soon post a better one & more as it develops.

Smaller, stubby, branching thorny Madagascan plant with cup-shaped yellow to gold flowers. Pretty cold sensitive- supposedly prone to ro...Read Moret if wet in winter cold. Leaves look rather typical of Pachypodiums- shine green and lancelote.