grow light duration on Universal
Quick answer
If your Universal has grow light duration, the most likely cause is: Succulents require 12-14 hours of high-quality light daily during active growth (spring/summer) and 10-12 hours during dormancy (fall/winter). Desert succulents evolved under 14+ hour summer photoperiods and CAM metabolism requiring prolonged light exposure for carbon fixation. Insufficient duration causes etiolation — elongated, weak growth as gibberellin hormones increase without regulation, causing pathological cell elongation as the plant desperately stretches toward photons.
Start here:
- 1. Set grow lights on timers: 12-14 hours daily from March-September, 10-12 hours from October-February
- 2. Avoid leaving lights on 24 hours — succulents need dark period for CAM carbon fixation and circadian regulation
Why Universal gets grow light duration
Succulents require 12-14 hours of high-quality light daily during active growth (spring/summer) and 10-12 hours during dormancy (fall/winter). Desert succulents evolved under 14+ hour summer photoperiods and CAM metabolism requiring prolonged light exposure for carbon fixation. Insufficient duration causes etiolation — elongated, weak growth as gibberellin hormones increase without regulation, causing pathological cell elongation as the plant desperately stretches toward photons.
How to reverse grow light duration on Universal
- 1
Set grow lights on timers: 12-14 hours daily from March-September, 10-12 hours from October-February
- 2
Avoid leaving lights on 24 hours — succulents need dark period for CAM carbon fixation and circadian regulation
- 3
Use timers with backup batteries to maintain schedule during power outages
- 4
Gradually adjust photoperiod seasonally (increase 15 minutes per week in spring, decrease in fall) to mimic natural light cycles
- 5
For dormancy-inducing species (Lithops, Haworthia): reduce to 8-10 hours in winter to trigger dormancy
Keep grow light duration off this Universal
Use automatic timers to provide consistent daily light periods; extend light hours in winter to compensate for natural daylight reduction; provide uninterrupted 6-8 hour dark period daily for CAM succulents to complete carbon fixation cycle.