There seems to be some confusion about exactly whether caldasii is in cultivation but with funnel shaped orange and red flowers this appears to be something very similar. Some people seem sure that it's B.acutifolia. The inner petals are orange/yellow, the outer are coral red. There are no other markings but the black anthers are prominent.
Untried outside, but like many Bomarea, the roots go so deep that they are unlikely to freeze in a normal UK winter. Climbing to about 2m, and dying down in winter.