How do I store peat-free soil mixes?
Written by
Michael Sullivan
Reviewed by
Prof. Martin Thorne, Ph.D.Peat-free soil mixes should be stored carefully to retain their structure and friends of microbes. I lost six months of compost blend because of mold in a damp shed! I learned my lesson: I now place my mixes in air-tight containers, and I avoid any moisture problems. Properly stored mixes should hold their nutrients from 6-12 months.
Container Selection
- Use 5-gallon buckets with gamma seal lids
- Glass jars for small seed-starting mixes
- Line fabric bags with plastic for breathability
Coir Brick Storage
- Keep in original plastic wrap until use
- Store below 60% humidity to prevent expansion
- Place silica gel packs nearby in humid climates
Compost-Based Mixes
- Use within 6 months for active microbes
- Freeze in portioned batches for 12+ month storage
- Label with mix date and ingredients
Keep your mixes in reusable silicone bags in the freezer so they don't dry out. If you're going to thaw, do it overnight, as I had a batch of mixes nearly ruined by microwaving, which heated the mixes to a point where it killed off the beneficial fungi. If you use a mix frequently, it may be best to keep them out in a 2-gallon countertop container with a breathable mesh lid that allows airflow but keeps moisture in.
Every month, I make sure to check the mixtures that have been stored. I open the containers to look for condensation or sour smells, which indicate the anaerobic decay of the mixture. Arguably my worst failure with this storage system occurred the first year when I forgot a bucket of worm castings mixture, the entire mixture sprouted mushrooms and nematodes after about nine months. I now label all containers with a "discard by" date.
Read the full article: 8 Peat Moss Alternatives for Healthier Gardens
