Dr. Bruce Bugbee debunks myths and answers FAQs on grow lights for cannabis based on his research so far at Utah State University’s Crop Physiology Lab (see time-stamps below to navigate topics) and the next video in the series here: https://youtu.be/JwtkHxv_3pU . Bruce is a world-renowned crop physiology professor famous for his work in controlled environment agriculture for NASA and is president of Apogee Instruments, a developer of research-grade instruments used in precision agriculture. Bruce’s lab at Utah State is one of the few with a license to study cannabis cultivation with several active research projects underway (see: https://www.usu.edu/today/?id=58336 ). The lab’s license is to research hemp, but these principles apply to marijuana, including sativa and indica. Some of Bruce’s answers in this video are based on what the research is showing so far, but further tests are underway. As this is a very hot topic right now, we will do our best to monitor questions posted in the comments below and ask Bruce to answer them in future videos.
Timestamps of topics covered:
2:24 Light as one of the nine cardinal parameters
4:04 Can too much light cause problems with my cannabis plants?
5:30 How far should my lights be above my cannabis plants?
9:30 What is the optimum light intensity for growing cannabis?
16:59 PAR and PPFD explained
19:30 The best DLI (Daily Light Integral) for Cannabis
24:25 The proper tools to measure light levels
26:40 DLI levels for seedlings/cuttings
27:20 Photo periods and light pollution thresholds during dark periods
30:20 New light pollution sensors
31:30 Light requirements of different cultivars
32:50 Light quality effect on the synthesis of cannabinoids and terpenes
34:17 UV and Far-red effects on cannabis
39:40 Optimal spectrum for veg and flowering
42:52 Design Light Consortium (DLC) and light efficiency listings
* Dr Bruce Bugbee’s bio: https://en.wikipedia.org/wiki/Bruce_Bugbee https://psc.usu.edu/directory/faculty/bugbee-bruce
* Apogee PPFD Handheld meter version – https://www.apogeeinstruments.com/mq-500-full-spectrum-quantum-meter/
* USB Smart Sensor version – https://www.apogeeinstruments.com/sq-520-full-spectrum-smart-quantum-sensor-usb/
* All other models – https://www.apogeeinstruments.com/quantum/
Apogee PAR-FAR and Red – Far-red sensors: https://www.apogeeinstruments.com/red-far-red-and-par-far-sensors/
Apogee microCache Bluetooth micrologger: https://www.apogeeinstruments.com/microcache-bluetooth-micro-logger/
Design Light Consortium: https://www.designlights.org/