The Grizzly Bear Prickly Pear, Opuntia erinacea ursine, is a distinctive cactus species known for its unique, fuzzy appearance. This common name comes from the dense, hair-like spines covering its pads, which resemble a bear’s fur. Native to the arid desert regions of the southwestern United States, this plant offers unique ornamental appeal.
Unique Characteristics and Identification
Opuntia erinacea ursine exhibits specific physical attributes that make it easily recognizable. Its pads, which are flattened stem sections, are typically oval to round and green, sometimes with purple or reddish hues. These pads are covered with two types of spines: larger, more traditional spines and fine, hair-like prickles known as glochids. The abundance of these glochids and long, flexible, often brown to reddish-brown spines creates the plant’s characteristic fuzzy, bear-like appearance.
This cactus can form substantial clumps, reaching heights of up to 2 feet and spreading horizontally up to 10 feet. In late spring to early summer, the plant produces vibrant yellow flowers, though some varieties may have pink or rose-colored blossoms. After the flowers fade, purplish fruits develop, which are edible and can be attractive to local wildlife.
Cultivation and Care
Successful cultivation of Opuntia erinacea ursine relies on providing conditions that mimic its native desert environment. Adapting to its specific needs ensures healthy growth and minimizes potential issues.
Light Requirements
This cactus thrives in bright light conditions, requiring at least 6 to 8 hours of direct sunlight daily for robust growth. Placing it in a south or west-facing location is ideal when growing outdoors or indoors. Sufficient light also encourages blooming and prevents leggy, stretched growth.
Soil and Drainage
Well-draining soil is crucial for the health of Opuntia erinacea ursine to prevent root rot. A sandy or gritty cactus/succulent potting mix allows excess water to drain quickly, mimicking its natural arid habitat. If planting in the ground, amending heavy soils with sand or grit improves drainage significantly.
Watering
Opuntia erinacea ursine is drought-tolerant and particularly susceptible to overwatering. It is important to water deeply only when the soil has completely dried out between waterings. During the active growing season in spring and summer, watering every 2 to 4 weeks is generally sufficient. Watering should be significantly reduced during the dormant winter months, often to once every 6 to 8 weeks.
Temperature and Hardiness
This cactus tolerates high temperatures and is notably cold-hardy for a cactus. It can thrive in USDA Zones 5 through 9, tolerating temperatures down to -30°F. Protection from extreme frost is important in colder climates to prevent pad damage.
Fertilization
Opuntia erinacea ursine is not a heavy feeder and generally requires minimal fertilization. During the growing season in spring and summer, a light application of a balanced, low-nitrogen fertilizer every 4 to 6 weeks is appropriate. Fertilizing should be avoided entirely during the plant’s dormant period in fall and winter.
Propagation
Propagating Opuntia erinacea ursine is most commonly achieved through stem cuttings, specifically from its pads. To propagate, carefully remove a healthy pad from the parent plant, making a clean cut at the joint. The removed pad should then be allowed to callus for several days to a week in a dry, shaded area. Once a callus has formed, plant the pad about one to two inches deep in a well-draining cactus mix, burying the lower third for stability. Water sparingly until roots develop, which can take several weeks, as the pad contains enough moisture to sustain itself initially.
Common Issues and Troubleshooting
Gardeners may encounter a few common problems when caring for Opuntia erinacea ursine. Overwatering is a frequent cause of soft, mushy pads and root rot, which can be identified by a rotten smell or discolored, mushy roots. To address root rot, remove the plant, trim away any affected roots, allow the trimmed area to callus, and then repot in fresh, well-draining soil, watering very sparingly afterward.
Pest infestations, such as mealybugs and scale insects, can occasionally affect the plant. These can be treated by inspecting the plant regularly and promptly treating infestations with insecticidal soap or neem oil. A lack of flowering is often due to insufficient light or an inadequate dormancy period, so ensuring proper sun exposure and reduced winter watering can encourage blooms.