PlantFiles: Pachypodium
Pachypodium bispinosum

When I bought one as a very small 2" potted plant,it right away showed vigor outdoor's in a pot. The next year I planted it in ground and it bloomed that summer. This winter it sent up a few blooms in January. It has showed no effects of 30f nights. Their cannot be many hardier Pachypodiums.

I can't fully second Bob's remark about outdoor cultivation.
My 3 plants are planted in the ground unprotected for 8 years now and didn't ever suffer due to rain in winter though living in a very slowly draining clayish soil.
Only the branches are suffering when we have a cold spell for several days, e.g. 4 nights in a row with lows down to 24 F.

Jordi

Interesting Pachypodium with a remarkable caudiciform trunk. The rest of the plant isn't as interesting as most other species, but if you love 'fat plants' this one's for you. It is a S African native and is particularly prone to rot if allowed to get too wet in winter (in a pot... at least that's been my luck). I have had several of these (though not nearly as caudiciform as in the photos) in the yard, and they do tend to rot in cold winters, but if kept in really well draining soil and given some overhead protection in frosts, will do OK in zone 9b. THey grow pretty fast for Pachypodiums