How should I store these amendments?

Proper Storage Techniques help ensure that the effectiveness of your soil amendments is extended for years. Soil amendments, such as vermiculite and perlite, will break down if they are exposed to moisture and/or extreme temperatures. I know this from experience; I once lost a batch of one of these materials due to humidity (remember the tropical storm). Following these techniques will also save money, and you will be able to maximize effectiveness over time after the season.

Temperature control inhibits degradation of material. Store amendments at temperatures lower than 80°F (27°C) in dark, cool spots, such as a basement or closet. My garden shed is cooler due to reflective insulation. Avoid using attics or garages, where temperature swings change significantly throughout the year.

Moisture control maintains functionality. Silica gel packets remove moisture from the ambient humidity inside containers. I change them every six months for maximum effectiveness. Check materials once a year for clumping, which indicates moisture has compromised the contents and should be corrected immediately.

Proper stacking practices will minimize risks of accidents and contamination. Place the heavier vermiculite containers closer to the ground. Stack the lighter perlite bins on top of each other. I keep mine by type and expiration date. This way, spills are prevented, and inventory is much easier to keep track of.

Long-term retention requires periodic care. At least once a season, check perlite or vermiculite before using it. If it has mold or an unusual smell, discard it. My five-year-old perlite works fine because I've stored it properly. Vermiculite lasts approximately the same amount of time, provided it is stored properly.

Read the full article: Vermiculite vs Perlite: Ultimate Comparison