Can I grow cactus outside in Denver, Colorado?

Gardens & Landscapes October 17, 2011|Print

Yes. There are a variety of cacti that can be grown in Denver's climate. Here are a few tips to get you started. First on your agenda is to determine the location of your cactus garden. Cacti require full sun, which is the equivalent of about five hours a day. An area on the south side of a house or garage is excellent, and if the garden can be close to a dwelling, even better. The heat collected in the walls will help raise the temperature in the surrounding area. Large rocks placed at random also will help raise the temperature. They also will add to the overall appearance of the garden. It is best to plant your cactus garden in April, May or June. This will give your plants all summer and fall to get established before winter. Good drainage is essential, so walls, steep banks or rock outcroppings are excellent choices for planting sites. If these natural conditions do not exist in your yard, do not be discouraged. A raised bed can be created with logs, railroad ties, timbers or boulders. Fill the bed with a mixture of 50 percent soil, 25 percent course sand, 15 percent pea gravel and 10 percent organic material. Cacti do not need the same amount of water as your lawn, so be sure to adjust your sprinklers accordingly. A normal amount of rainfall should be enough for most winter-hardy cactus. In the heat of summer, if you garden does not receive any rain for several weeks, supplemental watering may be needed.

The following is a short list of cacti that will do well in the Denver area:

  • Echinocereus reichenbachii
  • Echinocereus triglochidiatus
  • Escobaria missouriensis
  • Escobaria vivipara
  • Opuntia clavata
  • Opuntia compressa
  • Opuntia erinacea
  • Opuntia fragilis
  • Opuntia phaeacantha
  • Opuntia polyacantha
  • Opuntia imbricata
  •  

If you would like to look at some of these options, both Denver Butterfly Pavilion and the Denver Botanical Gardens display winter-hardy cacti in their gardens.