Nitrogen is one of the main three macro nutrients nitrogen phosphorus potassium npk required by plants and can often become the limiting factor to growth in a flourishing system flourish nitrogen is a concentrated 15 000 mgl blend of nitrogen sources it provides nitrogen in both the nitrate form and the plant preferred ammonium form however no free ammonia is released because the ammonium in flourish nitrogen is complexed and unavailable until utilized by the plantsr flourish nitrog