Let’s see. For Echinocereus I selected viridiflorus, reichenbachii, fendleri, engelmanii, and chloranthus. I also currently have a triglochidiatus growing from the last time I started seeds. For Escobaria, I have missouriensis, but sneedii and vivipara are also supposed to be good bets. Pediocactus simpsonii is supposed to be extra hardy, but it needs cold stratification which I didn’t feel like dealing with this time.
There are also a lot of Opuntias and Cylindropuntias that are cold hardy; these tend to be more forgiving of wet conditions.
My general strategy is to pick collections from farther north (for cold tolerance) and east (moisture) in their ranges, or from higher elevations. A lot of these are hardier than their current ranges would suggest. The big trick is keeping them relatively dry in the winter. Wet feet is a bigger problem than cold, so you need excellent drainage. Some of the more sensitive species really benefit from something to keep the rain and snow off in the winter.
Basically, you can set them up like alpines. A 1:1:1 mixture of builders sand, pea gravel and native soil is usually a good start. Put it in a raised bed at least 6" high, but more is better. A 1-2"mulch of gravel is also a good idea. When you plant, make sure it’s plenty warm. Do not water them in and keep them dry for at least a few days to allow any wounds to heal over.
One more thing. If you find yourself in Northampton, MA, Smith College has (or at least had) cactus growing outdoors on the south side of the conservatory and in some of the alpine beds
i hadnt noticed that, but Ill be sure to look next time. Its been several years since Ive been, but its been a favorite spot to go, especially in the depths of winter. Nothing like sitting under a 20 ft tall cacao tree in new england around February
I’ve tucked all the cactus into wooden frames which will go up against the house for winter under some straw. I don’t want them to spread in the yard so much, but want them to make it to spring. all the pads I’ve gotten have rooted well, one even filled a gallon pot from a tiny pad. hoping for nopales to eat next year if not fruit.
I have Desert Dream and Desert Glow in an unheated greenhouse. After a week of subfreezing temps part of Desert Dream has goo-ified. Desert Glow is looking ok (left part in the following picture).
