The Echinocereus reichenbachii complex consists of five basic varieties/sub species. (note depending upon the source) The varieties are ; ssp. reichenbachii, ssp. albispinus, ssp. armatus, ssp. baileyi, and ssp. fitchii. (However many synonyms abound) -These are small cylindrical cacti from the Southern Great Plains states. They can have a single stem or form small clusters of upright stems. Their habitat is varied but they are basically cacti of the southern grasslands and scrublands of eastern NM, western TX and extending north into western OK and southern CO.
Echinocereus reichenbachii are sensitive to overwatering and need very good drainage to avoid rotting. They do require more summer moisture than true desert cacti to grow and produce flowers. They need to be kept dry and cool in winter. E. reichenbachii are very cold resistant from -10° to -25° C and can take lower temperatures for short periods of time. In the fall they will lose a lot of moisture an shrink in size. They become limp, soft, and lean over, this is normal. If you grow them in a container, resist the urge to water them and store them in a cool dry place. (closet, basement, entry, porch, or shed....)
Here are the subspecies I grow
1 Echinocereus reichenbachii ssp. armatus
2 Echinocereus reichenbachii ssp. reichenbachii
3 Echinocereus reichenbachii ssp. albispinus
4 Echinocereus reichenbachii ssp. baileyi