I know the tree. I don't think it will grow north of zone 9, probably not north of 9b. It is a big, beautiful, fast growing flowering tree for the subtropics.

I was curious so Googled, and this site states it is possibly root hardy to 20 degrees F. Also known as the Kapok tree. I think I remember reading that seedpods are filled with fluff which was once used to stuff vests for life preservers...interesting. josh

Here is a link that might be useful: Silk Floss Tree

Thanks for the information! Looks like I'm out of luck growing this tree in zone 7b.

Common names are not always reliable but I think you are mixing up two related species, Josh. The kapok tree is Ceiba pentandra. It is a beautiful, huge tree with white flowers that are not terribly showy. The name, silk floss tree, is usually applied to Chorisia speciosa. This is the green-trunked tree, often spiny, with large, showy pink flowers.

The Chorisia is not wind-hardy like the kapok tree is. You'd need a greenhouse to grow one.
kevin