Outside succulents and cactus
What succulent and cath can survive a Castle Rock Colorado winter?
Douglas County Colorado
Thank you for your question. Depending on what part of Castle Rock, CO, you are, you are either in zone 5b (-15 to -10) or 6a (-10 to -5). Succulents and cacti don't fit into a 'one size fits all' category, so I suggest you go through the list of succulents found in the following article, to see if their USDA zone tolerances are at least 5. If they are below 5, the plants will not survive in typical Castle Rock winters: https://www.gardeningknowhow.com/ornamental/cacti-succulents/scgen/succulent-plant-info.htm