Potatoes are a rewarding crop that will give you a high yield as long as you provide them with the right growing conditions. Once planted, they need minimal tending until harvest time. Best of all, potatoes store well so you can enjoy your harvest for months (melting potatoes, anyone?). Here's how to grow potatoes at home, from planting, to watering, to hilling potatoes, to harvesting potatoes.
When to Plant Potatoes
Potatoes are cool weather crops and can be planted in the early spring as soon as the soil is workable. Although they like cool temperatures, they do not like freezing temperatures. Plant them as soon as the soil reaches 45 degrees Fahrenheit, or two to three weeks before your last frost date. Potato plants can tolerate a light frost, but you will need to cover the plants with some protection if your area gets a late-season heavy frost.
How to Prepare the Garden
Potatoes are root vegetables that will grow deep into the soil, so they grow best in loose, well-draining, slightly acidic soil. Heavy clay soil retains water and gets hard when it dries, making it hard for tuber-type plants to grow. Potatoes can be grown in-ground and in raised garden beds, containers, or grow bags. Potatoes require a location that gets six to eight hours of sunlight per day. Mix compost or fertilizer into the soil before planting.
Planting Fresh Seed Potatoes
Grocery store potatoes are not always suitable for use as seed potatoes, or potatoes that are planted to produce more potatoes. Although they can be planted in the garden, there is no way to guarantee that the potatoes haven't been treated with a fungicide or other chemicals to prevent sprouting. Seed potatoes sold by nurseries or seed companies are certified disease-free and are not treated with chemicals. For best results, use fresh seed potatoes. They will give you better yields, are less prone to disease, and offer you a larger variety of species not found in the grocery store.
How to Prep Potatoes for Planting
When you get your seed potatoes, they will probably not have sprouts yet. A week or two before planting, place the potatoes in a sunny area with temperatures between 60 to 70 degrees Fahrenheit to encourage sprouting. A day or so before planting outdoors, use a sharp, clean knife to cut the seed potatoes into 2-inch pieces. Seed potatoes smaller than 2 inches can be planted whole. Each piece must contain an eye or bud. Allow the cut potatoes to callous over. This step will help improve rot resistance and water retention once planted.
How to Plant Potatoes
Potatoes are grown using a "hilling" technique. The seeds are planted deep, and the stems are buried gradually by hilling up additional soil around the plant as it grows upward. Dig a trench at least 6 to 8 inches in the ground. Plant the potatoes cut-side down with the eyes pointing up, spaced 12 to 15 inches apart. Rows should be planted at least three feet apart. Cover the potatoes with 4 inches of soil. Once the seedlings emerge, add a layer of mulch to conserve moisture, help with weed control, and cool the soil.
Once the plant grows to about 6 inches tall, you can start hilling them. Mound the soil around the plants and continue to do so as they grow. The goal is to bury one-third of the plant. The buried stems will produce more potatoes. Theoretically, you can continue to hill the potatoes as much as you want. However, rain and wind will erode the hills unless you use rocks or bricks around the hills to prevent erosion. Continue hilling until the potato plants bloom and the aboveground part of the plant is at least a foot tall.
Hilling potatoes is an important part of growing potatoes. Tubers that are exposed to sunlight for a long period of time will turn green and produce solanine, a toxic compound that induces nausea. Although it's considered toxic, you would have to consume a large amount of the compound to experience side effects. However, it's better to be safe than sorry.
Potatoes like even moisture. The plants need 1 to 2 inches of water per week. Inconsistent water will lead to misshapen tubers. When the foliage starts to yellow and die back, decrease watering.
How Long Does It Take to Grow Potatoes?
Potatoes are ready to harvest in 70 to 90 days, depending on the variety. The tubers are ready to harvest when the foliage begins to die back. However, you can harvest "baby" potatoes about two to three weeks after the plants are done flowering. Carefully dig around the plant and only remove a few potatoes you plan to eat immediately.
How to Harvest Potatoes
Potatoes you plan to store should not be dug up until two to three weeks after the foliage dies back. Wait for a few days of dry weather before you harvest. Use a sturdy garden fork to carefully dig potatoes. After harvesting, allow the potatoes to lie in garden soil for two to three days. This step allows the potatoes to start the curing process, which will help the potatoes to last in storage longer. If the weather forecast calls for wet weather, you can also cure the potatoes in a protected area like a garage or covered porch. The potatoes will need to cure in a dry, cool, dark place (45 to 60 degrees Fahrenheit) for up to two weeks.
The Best Way to Store Potatoes
Potatoes can last for months as long as you provide plenty of ventilation, cool temperatures, high humidity, and no light. Store the potatoes in a cool area (between 42 to 55 degrees Fahrenheit). Warm temperatures can encourage sprouting and disease. Typically, an unheated basement or garage is ideal, but if you live in a warm area, consider storing potatoes in an extra refrigerator to set a temperature higher than normal.
Dealing With Common Pests and Diseases
Although potatoes are easy to grow once established in the garden, there are some common pests and problems that you may encounter.
Colorado Potato Beetle: Adults and larvae feed on potato foliage. Pick them off or use BT (Bacillus thuringiensis) spray, found at garden supply stores, to kill larvae.
Flea Beetle: Tiny black or brown insects that damage foliage. Use row covers early in the season as soon as you see evidence of the pests. Flea beetle populations can be maintained by crop rotation and maintaining high soil organic matter.
Aphid: Tiny insects that damage plants by sucking juices from the leaves and stems of plants. Insecticidal soap sprays are an effective control.
Diseases and fungus: Weather plays a large role in triggering certain diseases and fungus in the garden. Scab, a fungus, is the most common issue that damages a potato crop. Scab can live in the soil for years. Blight is another disease that affects potatoes. The best way to manage fungus and disease is to practice crop rotation, keep your soil healthy, and only use certified seed potatoes.