Growing Cactus in Zone 6a

Originally I wanted to grow cactus for food and fodder but Opuntia ficus-indica doesn't survive outside in zone 6. One site said this variety is cold hardy down to zone 6, but I tried and they all died. Since then I have tried many types, usually trying types that have largish pads and have accumulated about 30 types. In 2022 the temperature dropped to -8 F with 20mph winds and even a few that had made it in previous years took damage or died.

We found a patch of Opuntia fragilis growing on the property but as the name implies they break off easily and the thorns can easily go all the way through your shoes. They never bloomed for me and are a hazard so I got rid of them.

Opuntia humifusa (Eastern Prickly Pear)

These are very vigorous and I have two variations with varying intensity of yellow and orange in the center. They are very easy to grow but can sometimes suffer cold damage. Interestingly, they lie down flat on the ground in the winter under the snow and raise themselves back up into growing position by themselves the next spring.

Opuntia phaeacantha Hybrids

These are vigorous and fairly cold hardy. I have one that has an orange center that fades to peach that has gotten several feet across and 18" high. It is a prolific bloomer and I never saw any cold damage till the last winter where a few pads had to be discarded in spring.

Opuntia gilvescens

These are vigorous with big yellow flowers but most winters will suffer some damage. I have moved mine into a less noticable area far from my regular cactus garden. These also tend to lay down a little in the winter.

Opuntia aurea

These grow a little slower but are very cold hardy. Most suffer no damage but one 'Gooseberry' had enough water content in the pads to split open. Other than being split they were alive and I replanted them.

Cholla

I was hoping to grow some cactus that gets taller than 2' and tried various types of cholla. Most cholla are not that cold hardy but some Cylindropuntia imbricata varieties can tolerate some cold. I bought a 'very cold hardy white' cholla and it has grown almost 2' tall but is actually dark pink. Another two, Purple Haze and Horts Spineless, are alive but not thriving. A Giant Creeping Form, Snow Leopard, and Golden Lion are doing okay despite the coldest winter since 1948. Other regular Cholla imbricata, Giant Form, and Parrot Cholla are not cold hardy enough.

• Cylindropuntia imbricata (best cold hardy and sold as a white but actually deep pink)
• Purple Haze (survives barely year after year)
• Horts Spineless Cholla (survives barely year after year)
• Snow Leopard (hardy)
• Giant Form Creeping Cholla (hardy)
• Golden Lion pencil cholla (surviving)
• Cylindropuntia imbricata deep pink (not hardy died)
• Cylindropuntia imbricata light pink (not hardy died)
• Cylindropuntia imbricata Giant Form (not quite hardy enough died)
• Parrot Cholla (not hardy died)

Most of the cholla have died as they can't survive winters in zone 6a. We had -13°F winter 23/24 and many of the cactus took damage and large parts of the Phaecantha hybrid metioned above died. I have propagated some to new locations and some have done better that the original.