This quantity will enhance the growth and vitality of approximately 20 house plants for 1 year. 5 lbs of Rock Dust remineralizes approximately 5 square feet of garden area. | This quantity will enhance the growth and vitality of approximately 40 house plants for 1 year. 10 lbs of Rock Dust remineralizes approximately 10 square feet of garden area. | 20 lbs of Rock Dust remineralizes approximately 20 square feet of garden or greenhouse area. | 70 lbs of Rock Dust remineralizes approximately 70 square feet of garden or greenhouse area. |