For those of you who plant in a lot of containers, this is a must have to save you up to 50% on your watering time. This product was originally developed to assist commercial growers, nurserymen and interior/exterior landscapers in growing and maintaining vigorous plants with fewer waterings. These polymer granules, when mixed into the soil, absorb and retain water like a sponge. When the soil begins to dry and there is no longer any capillary water, the stored water is slowly releases back to the plants root system. These polymers do not contain any fertilizer, and last 3-5 years in the soil. Only a minimal amount is needed for each container, so this bag should last you awhile.