I have a Pachypodium inopinatum which is about 4" across with 5 or 6 short arms on it, bout 7" tall. Had it for 3 years. Noticed recently it's hollow, a little shriveled on the trunk but it's been this way for at least 5-6 months.. Pulled it out of it's pot and got basically no roots except close thick touching it. It's been growing very well, new leaves all the time even flowered at least twice maybe 3 times in past 6 months. Question is; is it a goner since it's hollow? Trunk walls couldn't be more then 1/4" thick. Was going to cut it open just below the arms to try to save it from rot but there would be not much left worth saving. Do hollow, really hollow Pachypodium's survive. I've been trying this past winter not to water it much and hardly ever feed it, so I was thinking it's been living of the plant material inside. Tempted to really start heavy fertilizing it to try to get it to fill the inside back up but could cause it to "rot" faster if that's the problem. There is no sign of rot on the outside except no hanging down roots and the truck is a tan color instead of the normal white course this could just be normal. Thanks for your advice
It might not be rot, but rather dehydration. However, if you've been watering regularly, then I would suspect rot and it is unclear if you will be able to save it. If the roots have simply died from dehydration, then you can use some root stimulating hormone and then slowly introduce water. Fertilizing probably will not help due to the lack of roots.
