Visionary Cactus Guide
O. denegrii -
A rare 7 cm high cactus that resembles an inverted green pine-cone with a wooly center, laying in the rocks. Has triangular tubercles arranged in overlapping spirals. Fall blooming, with pink flowers and a large taproot. Sacred to several Mexican Indians. Another type of "living rock" Cactus. Native to Tamaulipa, Mexico.
Will not tolerate cold nor will it graft well. Needs full Sun.
Contains: horenine (.002%), tyramine (.003%), N-methyltyramine (.0002%).