By following a few basic techniques, you can coax more bountiful yields from your potato plants.
First, start with certified seed potatoes of a prolific variety like 'All Blue', 'Red Norland', or 'Yukon Gold'. In early May or a few weeks before the last expected frost, prepare a bed of loose soil by digging in three 5-gallon buckets of compost. Dig a trench 10 inches deep and space the seed tubers 10 inches apart along the bottom. Cover each row with 4 inches of soil topped by a thin layer of mulch, such as pine needles.
When the sprouts reach 6 inches tall, mound soil around them in the trench, covering up the lower half of the plant; do this again when the stems grow another 6 inches. This mounding process encourages root formation above the seed tuber. After plants blossom, begin harvesting new potatoes. For reliable seed potatoes, order from Bigelow Associated Farms (719/754-3640) or Irish Eyes-Garden City Seeds (877/733-3001).