I just heard of a tip I want to try and see if anyone has tried this. Often I find that my onion powder and garlic powder harden over a short period of time. Someone suggested using those little desiccant packets found in medicine bottles. They prevent the powders from drying up. One tip that I know works is wrapping celery in foil keeps it fresh longer. This works for cucumbers too. Keeping mushrooms in a small paper bag seems to extend their life. That's all I have,