Maximum Yield USA December 2016 | Page 86

BALANCING PGR PRINCIPLES S tarting with the basics, PGR stands for plant growth regulator, sometimes also referred to as a plant hormone. Every plant naturally produces very small amounts of hormones in order to control its normal functions such as root growth, height, node and internode growth, flowering, quantity of flowers, fruit, and any other developmental growth. Plant growth regulators are a chemical or mix of chemicals that make a plant change beyond its naturally physiological growth actions, through the cells, organs, and tissues. It does this by either slowing down the rate of growth or maturation; speeding up the rate of growth or maturation; or altering the natural behavior of a plant. Note that this does not include any substances which are intended as a plant nutrient, including trace elements, plant inoculants, or nutritional chemicals. Plant growth regulators are a chemical or mix of chemicals that make a plant change beyond its naturally physiological growth actions. 84 Maximum Yield USA  |  December 2016