Winter Dormancy on echinopsis
What's Happening
Cactus dormancy is primarily thermoperiodic (temperature-triggered) rather than photoperiodic. When ambient temperatures consistently drop below 15°C (59°F), metabolic activity slows dramatically, triggering facultative dormancy. This is an evolutionary adaptation to arid desert winters where cold nights coincide with dry conditions.
How to Fix It
- 1
Identify your goal: dormancy for natural rest cycle OR active growth for year-round development
- 2
For dormancy: Move cactus to coolest available indoor location (unheated room, garage, or basement) maintaining 7-13°C
- 3
For active growth: Maintain temperatures at 20-25°C (68-77°F) with supplemental full-spectrum grow lights 12-16 hours daily
- 4
Measure temperature at plant level (not room level) - heat vents and windows create microclimates
- 5
Track temperature trends for 3-5 days before deciding on winter care strategy
How to Prevent It
Monitor indoor temperatures with a thermometer. If maintaining active growth, keep temperatures above 15°C (59°F) consistently. If inducing dormancy, relocate to an unheated area where temperatures range 7-13°C (45-55°F).