A reader's mistletoe cactus (Rhipsalis) that thrived for over five years has started turning brown, with strands falling off. Despite repotting into a slightly larger pot without drainage holes and adding a gravel layer, the plant continues to decline with weekly watering.
The diagnosis is insufficient hydration. Cautious watering can leave soil superficially damp but dry at deeper levels, causing browning stems, shrivelling, and segment loss due to moisture stress at the roots.
The prescription is to repot into a container with drainage holes, or use a nursery pot inside a decorative one, with succulent or cactus compost. After repotting, water thoroughly until water flows from the holes, then allow the soil to dry out somewhat between waterings—typically every one to two weeks. Mistletoe cacti need consistent moisture but good drainage, as they detest waterlogged conditions.
Prevention involves ensuring pots have sufficient drainage holes and regularly checking soil moisture a few centimetres down to accurately judge watering needs.
