Page 18 - Griffin Gazette Issue 2 - 2021

HORTICULTURAL

LIGHTING

By Erica Hernandez, CEA GGSPro Technical Specialist
Horticultural lighting, and working to understand the science and terminology, can feel overwhelming. The array of lighting options,
from fixture sizes and shapes, electrical specs, wavelength, and intensity, is extensive. Which qualities are most important?
When discussing horticultural lighting, we refer to instantaneous light levels provided as µmol PPFD, calculate daily light integral
in mols, and define the electrical efficiency in µmol photons produced per Joule of electricity consumed. Every reputable lighting
manufacturer provides this information about their fixtures. Fixtures are also described as suitable for sole-source, supplemental, or
photoperiod lighting. What do these terms mean, and how do they relate to plants?
To make sense of this, first identify your lighting application. Warehouse and vertical farm crops rely on artificial lighting (sole-source lighting).
Sole-source lighting requires different considerations than supplemental lighting, day length extension or nighttime interruption even more so.

18 | GRIFFIN GAZETTE 2021