{"id":510,"date":"2025-12-16T10:16:08","date_gmt":"2025-12-16T15:16:08","guid":{"rendered":"https:\/\/site.extension.uga.edu\/dekalb\/?p=510"},"modified":"2026-03-10T09:21:33","modified_gmt":"2026-03-10T13:21:33","slug":"not-all-grow-lights-are-created-equal","status":"publish","type":"post","link":"https:\/\/site.extension.uga.edu\/dekalb\/2025\/12\/not-all-grow-lights-are-created-equal\/","title":{"rendered":"Not All Grow Lights are Created Equal"},"content":{"rendered":"\n
\n
\n
\"Lettuce<\/figure>\n<\/div>\n\n\n\n
\n

Grow lights are a popular lighting supplement used during darker months, or in homes with limited window access. While the standard fluorescent or LED lights found throughout our homes are designed for human vision, the spectral composition and intensity of grow lights are optimized for plant growth (Wu et al., 2024<\/a>).  <\/p>\n<\/div>\n<\/div>\n\n\n\n

How Plants Utilize Light<\/h2>\n\n\n\n

Light can be divided into different wavelengths, measured in nanometers (nm). The visible  spectrum extends from 380 \u2013 700 nm, with specific ranges appearing as different colors. Plants utilize chlorophyll pigments to absorb light between 400\u2013700 nm range, which is typically defined as the photosynthetically active radiation (PAR)<\/strong> range.  Within this, light is primarily absorbed in the blue (400-500 nm) and red (600\u2013700 nm) portions of the spectrum (Stamford et al., 2023<\/a>; Wu et al., 2024<\/a>). Beyond the visible spectrum, certain wavelengths of ultraviolet light have been found to stimulate plant defenses and aid in antioxidant and flavonoid production (Stamford et al., 2023<\/a>). Additionally, far-red light (700-900 nm) up to 750 nm can be utilized in photosynthesis and is sometimes included in the definition of PAR (Stamford et al., 2023<\/a>; Zhen et al., 2022<\/a>).<\/p>\n\n\n\n

\"A<\/figure>\n\n\n\n

Since pigments and photoreceptors regulating distinct cellular processes absorb light in different parts of the spectrum, the ratio of blue to red light can influence plant growth patterns (Wu et al., 2024<\/a>; Dunn & Mill, 2017<\/a>). This includes stem elongation, leaf development, and flowering. Blue light is generally associated with compact, vegetative growth, whereas red light typically promotes stem elongation and flowering. However, this varies among plant species (Dunn & Mill, 2017<\/a>; Runkle, 2017<\/a>). Although standard house lights emit light in the blue and red range, their output is typically too weak for effective plant growth.  <\/p>\n\n\n\n

Factors Influencing Grow Light Performance<\/h2>\n\n\n\n

Three main types of grow lights are available, including fluorescent lights, high-intensity discharge (HID) lights, and light-emitting diodes (LED)<\/strong>. Light quality, light intensity, energy efficiency, and heat emission vary significantly among them. <\/p>\n\n\n\n