PDA (potato dextrose agar) is the all-purpose default — works across most species and the safe first choice for any cultivator starting an agar workflow. MEA (malt extract agar) has a slightly richer sugar profile that favors oyster varieties and certain wood-loving fungi, often pushing them faster than PDA. Starting out, use PDA. Once you know which species you're working with, MEA may give a speed advantage on certain genera.

Sealed plates stay viable for about 4–6 months refrigerated. The agar slowly dries through the lid seal over time — fresher plates colonize faster and inoculate cleaner. Use within the shelf window for best results. Plates that show condensation, off-color, or surface films at receipt are reasons to set aside; reach out and we'll replace.

Refrigerate upon receipt, use as soon as possible. To inoculate: sanitize the dish exterior and your tools, briefly lift the lid in a clean environment, transfer your culture wedge or syringe drop, close the lid, and incubate in a clean environment at approximately 76°F. Avoid wide temperature swings. Keep plates sealed until ready to inoculate.

When volume justifies the workflow. Pre-mix powder drops the per-plate cost dramatically once you're pouring 20+ plates at a time, but requires a pressure cooker for sterilization and a flow hood or still air box for clean pouring. Most cultivators start with pre-poured plates and graduate to pre-mix powder once they're running 50+ plates per month.