Growing a successful potato crop in the Pikes Peak region is equal parts skill and luck.  Some gardeners would argue that luck is the primary ingredient, but knowing how to grow potatoes will certainly help!

Potatoes need a soil that is rich in organic matter and drains quickly.  A heavy, clay soil MUST be amended with well-rotted manure, compost or Canadian sphagnum peat moss if a potato planting is to be successful.  Fertilizer should be added before planting too, and phosphorus, which promotes tuber development, should be the primary nutrient.  A good 8-10-8 vegetable food is perfect for potatoes.  If straight fertilizers (instead of a mix) are to be used, two pounds of potash and three pounds of super-phosphate per 100-foot row is sufficient.  Mix all fertilizers thoroughly with the soil before planting.  Potatoes should be rotated in the garden every season and should not be planted in the same ground more frequently than every four years.

Planting only CERTIFIED SEED POTATOES will ensure disease free tubers at planting.  Large seed potatoes should be cut into small segments with at least two viable eyes per piece.  Lay the cut potatoes on paper in a cool, dry place and dust the cuts with a soil/sulfur mixture to hasten the formation of callus.  Callusing takes about 24 hours.  Purchasing “single drop” potato seed (when available) eliminates the need for cutting.

Potatoes can be planted three weeks before the last expected killing frost which is approximately May 15^th.  Plant the potato sets into trenches 5 inches deep and 12 inches apart with rows at least 2 feet apart.  Expect sprouts in three weeks.  Five to eight pounds of potatoes will plant a 100-foot row.

Potato beds should be cultivated frequently to eliminate weed competition and increase the oxygen content of the soil.  A soil mound or ridge should be gradually pulled over the top half of the plants to prevent light from striking newly formed tubers.  Potatoes should be irrigated regularly through the growing season but will not tolerate a waterlogged soil.  Organic mulches will help regulate soil moisture.

Harvest can begin when the potato tops have dried back although “baby” potatoes can be snitched throughout the season.  After digging, potatoes should dry only enough to gentle brush excess soil away.  Store potatoes in a humid place with a temperature of 37 to 45 degrees.

Potato plants should be dusted every two weeks with a dusting sulfur to prevent diseases that inhibit tuber growth.  Sevin dust will control the Colorado potato beetle and the assorted aphid and psyllid species that occasionally infest potatoes.   

For any questions you have on this article, or any topic of concern, email us—or better yet, come by and talk to one of our professional staff members.  Remember, Phelan Gardens is open year-round!    

For additional information, check the following links:

• Potatoes for the Home Garden
• Planning a Vegetable Garden
• Vegetable Root Crops