Opuntia chisosensis SB992 Brewster Co, TX

Opuntia chisosensis, Chisos Mountains Prickly Pear is a tough upright Opuntia with large cladodes that have a distinctive pale blue appearance and long golden spines. On new cladodes the spines emanate from the areoles on the upper portion. It is found at high elevations in the Chisos Mountains and east into Coahuila, Mexico - again at high elevation - in the Sierra del Carmen. This seed collection was gathered by prolific seed collector, Steve Brack.

Opuntia chisosensis is sometimes considered a variety of Opuntia lindheimeri, which itself is sometimes considered a variety of Opuntia engelmannii. As with all things Opuntia, taxonomy is a thorny issue. Regional variation and natural hybridisation further complicates matters. Observing regional origins and recording variational differences have always been at the heart of cactus collection best practice. It has always seemed to me more worthwhile to note these differences rather than lump together plants under one specific label. Growing both these species side by side at our nursery the differences between this Trans-Pecos collection of Opuntia chisosensis and a collection of Opuntia lindheimeri from east of the Pecos River are very obvious. Opuntia chisosensis has very distinctive glaucous cladodes and not the green cladodes of Opuntia lindhemeri. The cladodes of Opuntia chisosensis tend to be more obovate rather that those of Opuntia lindheimeri which tend to be larger and more obovate to orbiculate. And geographically and topographically there is no overlap between these two species. Opuntia lindeheimeri predominates east of the Pecos River in mesic soils and - in those few locations that it does occur west of the Pecos River - it is found in canyons. Opuntia chisosensis by contrast, is found on rocky ground at high elevations in the Chisos Mountains and the Sierra del Carmen. 

This is an Opuntia that has got everything going for it: a handsome upright habit, strong vigorous growth, golden-yellow spines contrasting against blue-grey cladodes, glochids that aren't too troublesome (as far as glochids go) and - most importantly of all - extreme cold tolerance that will see it surviving sub-zero temperatures down to about -15C if kept completely dry.

One of the best Opuntias for the cold wet and very variable growing conditions of the UK.