Plant growth enhancing mixture and method of selectively timing the application of same during the development of crop plants or other plants to positively augment cell number increase and cellular development of crop plants or other plants to enhance development and/or productivity of the economic portion of the crop plant or other plant. Application of the plant growth enhancing mixture at flowering enhances both weak flowers and normally strong flowers. The plant growth enhancing mixture and method of application have also been shown to impart varying disease resistance to the treated crop or other plants. The plant growth enhancing mixture and method of application also increases the depth and strength of rooting for greater access and transport of water and nutrients for growth and productivity of the crop plant.