How to grow monkey tail cactus
Overview
Monkey tail cactus (Cleistocactus colademononis) is a trailing cactus with long, soft white spines resembling a monkey's tail. It is grown for its unique ornamental form and produces pinkish-red flowers in summer. Needs bright, indirect light and very free-draining soil to avoid rot.
Soil Preparation
Use a very free-draining mix: 2 parts cactus potting mix to 1 part pumice or perlite. Ideal pH is 6.0–7.0. Avoid adding compost or moisture-retaining ingredients. A layer of gravel at the bottom of the pot helps drainage.
Growing Guide
Position in a hanging pot or basket where the stems can trail, in a spot with morning sun and afternoon shade. Use a cactus-specific mix with added pumice or coarse sand for drainage. Space plants 15–20 cm apart in a container; avoid overpotting. Water only when the soil is completely dry, and reduce watering in winter. Do not plant in garden beds with heavy clay soil.
Care
Feed with a diluted cactus fertiliser (low nitrogen) every 4–6 weeks during spring and summer. Prune only to remove dead or damaged stems. Repot every 2–3 years into fresh, free-draining mix; handle carefully due to fragile spines.
Companion Planting
Pairs well with other hanging succulents like string of pearls, burro's tail, and echeveria. Avoid planting near moisture-loving plants like ferns or impatiens that will keep the soil too damp.
Common Pests & Risks
Mealybugs are the main pest, appearing as white cottony masses on stems. Treat with a cotton swab dipped in alcohol or use neem oil. Rot from overwatering is the most common disease; ensure the pot has drainage holes and use a gritty soil mix.
Troubleshooting
Stems turning brown and mushy: overwatering or poor drainage — reduce watering and repot into dry mix. Stems shrivelling: underwatering — water when soil is dry. No flowers: not enough light — move to brighter spot with morning sun. Mealybugs: treat with alcohol or neem oil. Stems dropping: overwatering or cold damage — protect from frost.