Echinocereus triglochidiatus - Poncha Springs, CO 7700Ft
Echinocereus triglochidiatus or Claret Cup Cactus is one of the most cold hardy cactus. The seed for these plants was collected near Monarch Pass near Poncha Springs, Colorado. Plants were growing at 7700ft on a gentle east facing exposure. Red or Claret colored flowers appear in May to July and are Hummingbird Magnets. Plants pictured are what is for sale.
I do not guarantee these in a zone 4/5/6 because everyones growing conditions are different but this would be a good trial plant to grow in your cold outdoor garden. Try to plant outdoor 90 days before 1st hard freeze.