Q: I heard you on radio tell how to grow potatoes in perlite. Can you provide a printed reference?
A: It’s east to grow a perlite-filled plastic tub of Irish potatoes on a patio or deck! A large tub can hold 4 – 6 seed potatoes. Once set up, if you have a few days over fifty degrees, leaves will appear.
When stems are six inches high, I fill around them with more perlite. I fertilize regularly with water-soluble plant food. When the stems emerge from the top of the tub I’ll add a final layer of perlite and let the plants grow until June harvest time.
Details at Growing Potatoes in Perlite.
Note that the author plants her potatoes in the tub when it is almost full of perlite. I prefer to put six inches of perlite in the bottom of the tub, plant the seed potatoes, then gradually cover the stems as they elongate.