Did a little experiment for something to do. Bought potatoes put one in a closed box an put in front of window an put one under the sink here at school in the dark. Took them both 2 weeks to get sprouts but the one under the sink has bigger sprouts. These were just potatoes bought off the shelf at Wal-Mart. So about 2 weeks before I am ready to plant I am going to put some under the sink to sprout.