Question: I applied your products, as directed, and ended up with some extra. How long can I store your products without them losing effectiveness? Answer: John and Bob's GrowGreen products can be stored indefinitely as long as they don’t get wet. For Penetrate, store the two bottles as they are, with the contents separated. Once you mix these two components biological activity begins and the resulting blend should be used promptly. Also, once Nourish Biosol is opened, it should be used within 3-4 months. We have seen mold growth when not used within that time. The mold is not harmful, but we would prefer to avoid it.