The Opuntia microdasys albata, known as the white bunny ear cactus or polka dot cactus, is a popular houseplant. This succulent originates from Mexico and features flat, segmented pads resembling rabbit ears. It is covered in white, hair-like structures called glochids, which are tiny, barbed bristles. These glochids easily detach and can cause skin irritation, making the plant prickly despite its charming appearance.
Caring for Your Opuntia microdasys albata
This cactus thrives in bright, direct sunlight, ideally receiving six to eight hours daily. Insufficient light leads to etiolation, causing pads to stretch and become leggy. Indoors, a south or west-facing window is often the most suitable location.
The white bunny ear cactus prefers warm temperatures, generally above 50°F (10°C), and is not frost tolerant. Protect it from freezing temperatures by bringing it indoors in cooler climates. This cactus prefers dry indoor air and does not require high humidity.
Water using the “soak and dry” method, allowing the soil to dry completely between waterings to prevent root rot. Overwatering is a common issue; it is better to underwater. During winter dormancy, reduce watering significantly, often to once a month or less. A fast-draining cactus or succulent mix is ideal, often amended with perlite or pumice. Pots must have drainage holes to ensure excess water can escape.
Fertilize lightly and infrequently during the active growing season in spring and summer. Use a balanced, diluted succulent or cactus fertilizer, typically once a month or a few times during the entire growing period. Avoid fertilizing during the dormant winter months. Repotting is usually needed every one to two years, or when the plant outgrows its container. Choose a pot only one to two inches larger than the current one.
Propagating Opuntia microdasys albata
Propagating Opuntia microdasys albata from its pads is straightforward. Carefully remove a pad from the parent plant using tongs or thick gloves to protect your hands from the glochids. A sharp, sterile knife can be used to make a clean cut.
Once detached, allow the pad to callus for several days to a week in a dry, shaded area. This crucial step prevents rot when the pad is planted. After callusing, plant the pad upright in a well-draining cactus or succulent soil mix, burying the cut end about an inch deep. Alternatively, larger pads can be laid flat on the soil surface, where they will also root.
After planting, do not water until roots have formed. Once rooted, care for the new plant as you would a mature specimen.
Common Challenges and Solutions
Etiolation, characterized by stretched or leggy growth, results from insufficient light exposure. To correct this, move the plant to a location with more bright, direct sunlight. Severely etiolated growth can be pruned to encourage a more compact form.
Root rot is a prevalent problem, typically caused by overwatering or poorly draining soil. Symptoms include mushy or yellowing pads, a soft base, and a general decline in plant vigor. If detected, carefully remove the plant, trim away any rotted, mushy roots, allow the cut areas to dry, and repot in fresh, well-draining soil.
Common pests include mealybugs and spider mites. Mealybugs appear as small, white, cottony masses on the pads. Manage these pests by gently wiping them away with a cotton swab dipped in rubbing alcohol.
Pads shriveling often indicates underwatering, while pads becoming soft or mushy can signal overwatering. Adjust the watering schedule accordingly to help the plant recover.
Handling and Safety Tips
The Opuntia microdasys albata is covered in glochids, tiny, barbed, hair-like spines that easily detach and cause skin irritation. They are difficult to see and remove due to their small size and barbed nature.
When handling this cactus, use protective measures. Thick gloves, tongs, or folded newspaper can help prevent direct contact with the glochids. Avoiding direct touch is the primary safety tip.
If glochids get onto the skin, several methods can aid in their removal. Using sticky tape, such as duct tape, pressed firmly over the affected area and then quickly pulled off can remove many of them. Tweezers can be used for more visible clusters. Another method involves applying a thin layer of white household glue to the skin, allowing it to dry, and then peeling it off, which can lift embedded glochids.