Home gardeners have had to rely on proper storage conditions (cool and moist) to prevent potatoes from sprouting. But sprouting will eventually occur even if the gardener does everything right. Research by Mary Jo Frazier, Nora Olsen and Gale Kleinkopf from the University of Idaho have found products that should help home gardeners.
These researchers were looking for an organic method to control potato sprouts. They found essential oils from some herbs and spices to be effective sprout inhibitors. Specifically they found that spearmint oil, peppermint oil and clove oil suppressed sprouting by physically damaging rapidly dividing cells in the sprout. Each of these products is so safe that the FDA has approved them for addition to food.
Several application methods were considered though most were only suitable for commercial storage facilities. The only practical method for homeowners was one the researchers labeled a “low-tech” wick method. This was accomplished by placing a small piece of blotter paper saturated with spearmint or peppermint oil in a box with the potatoes. This method was not recommended for the clove oil. Though it was found that peppermint and spearmint oils were equally effective in suppressing sprouts, the peppermint oil was less likely to affect flavor of the potatoes. Reapplication at two- to three-week intervals will be needed for continued sprout suppression. Little to no residue was found on the potatoes from these products due to their high volatility. The first application should be done before sprouting occurs.
Blotting paper is much more difficult to find than it was in the past and so you may want to substitute blank newsprint. However, if blotting paper is desired, try herbarium supply houses. Blotting paper is used to press plant specimens. (Ward Upham)