Anthocyanins are secondary metabolites in plants that are responsible for the red and purple colors. However, anthocyanin concentrations can be impacted by many factors, including light quality, temperature, nutrient deficiency, carbohydrate status, root rot, overwatering, and drought. When an increase in anthocyanin concentration is observed, growers must determine which of the following possibilities are likely culprits for the change in leaf color.
From rooting to finishing, there are a wide range of reasons why petunias may display purple discoloration. However, the location of occurrence and the stage can help diagnose why the discoloration is occurring.
LED Blue Radiation Propagation for spring bedding plants occurs during the darkest days of the year from both a light quality and quantity perspective. As a result, many growers utilize supplemental lighting to promote plant growth. Growers have a wide range of lighting spectrum choices ranging from narrow bands (specific wavelengths of light) such as blue or red radiation to broadband (a wide range of wavelengths), which generally appear as white. When rooting under blue and red LED, growers may observe a purple discoloration of the foliage.
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