I used to start mine in flat trays but it seemed I was constantly misting to keep the soil and tubers from drying out. The only slight "damage" I had was the roots sometimes tangling together. So I placed them head-to-toe in the trays to keep the roots on opposite ends. I now start most of mine in gallon zip locks with potting mix. Most of the mix I buy is already damp enough without having to add any water. Seems to me that being enclosed in the bags creates a bit of humidity that starts growth faster. But I'd encourage being very frugal with water to avoid mold inside the bags. I hope to start putting those with sprouts into planters this coming week.
