Etiolated Growth on a Columnar Cactus

Abnormal Thin Growth on a 30-Year Cactus: Etiolation

A columnar cactus (purchased ~1992) in NYC showed no growth for years, then produced thin, pale top growth in the last year. Base is brown and hard (corking).

Diagnosis

New growth is etiolated—stretched, weak, pale—due to insufficient light. The plant "searched" for light. This growth is permanent and cannot support future thicker growth.

Plan

• Move to south-facing window; keep cool, no water until spring.
• Spring: repot in soilless mix, resume watering slowly.
• If new growth widens, the narrow etiolation zone may buckle.
• Option: in spring, cut off etiolated top, callous, and root as new plant.

ID Note

Likely a columnar cactus (e.g., Cereus), but abnormal growth complicates ID.