A semi-tropical legume originally from Brazil, peanuts (Arachis hypogaea) are also called groundnuts because the nuts grow below the ground. A peanut plant needs at least 100 days of warm weather to make a mature crop, but fast-maturing Valencia or Spanish peanuts can be grown in the north. Growing peanuts is easiest in climates where both days and nights stay warm in summer, such as the Southeast. Peanuts require full sun and soil temperatures above 65 degrees Fahrenheit.
Types of Peanuts
Valencia peanuts are the most popular type for the home gardener. The fastest maturing Valencia varieties are often ready to dig 100 days after planting. Famous for their sweet flavor and well-filled pods, each pod usually contains three to five seeds. Varieties include ‘Georgia Red,’ ‘New Mexico Valencia’ and ‘Tennessee Red.’
Spanish peanuts produce small, rounded nuts with fine flavor and a crisp texture when roasted with oil. Maturing about 110 days after planting, Spanish peanuts have an erect growth habit with good drought tolerance. Varieties include ‘Early Spanish,’ ‘Carolina Black’ and ‘Shronce’s Black.’
Runners are sprawling varieties that grow best in the Deep South. Maturing in 130 to 150 days, disease-resistant varieties such as ‘Southern Runner’ and ‘Georgia’ produce medium-sized kernels, two to a pod, beneath vigorous, spreading peanut plants.
Virginia peanuts are a little more restrained than runners, but they still need 130 to 150 days of warm weather to make a crop. These are the big peanuts found in snack foods, or sold as freshly roasted peanuts. Varieties include ‘Carwile’s Virginia’ and ‘Virginia Jumbo.’
How to Plant Peanuts
Peanuts grow best in slightly acidic, sandy soil with a pH between 5.8 and 6.2. Plant peanuts at least two weeks after the last frost has passed, when the soil is warm. Wait until just before planting to remove the seeds from the shells. Rather than applying pre-plant fertilizer, it is best to plant peanuts after a heavily fertilized non-legume crop such as corn or cabbage.
Sow peanut seeds 2 inches deep and 6 to 8 inches apart, with at least 24 inches between rows. Thin seedlings to 12 inches apart. Peanuts also can be grown in hills, with three plants per 3-foot-wide hill. You can interplant peanuts with spring radishes or lettuce to suppress weeds.
For recommended planting dates for your local climate — and to design your garden beds — try our Vegetable Garden Planner.
Keep your actively growing peanuts thoroughly weeded, and hill up loose soil around the plants when they are 12 inches tall. About six weeks after planting, peanut plants produce pea-like yellow flowers on stems that grow longer each day. When fertilized, the flowers become pegs that bend over until their tips penetrate the soil. Peanuts develop underground, at the ends of these pegs.
You should wait to harvest your peanuts until the plants begin to die back and the soil is warm and dry. Loosen the soil with a digging fork, and then use two hands to lift intact peanut plants with stems and roots attached.
After harvesting peanuts, shake off the soil and lay the plants in the sun to dry. Let the harvested plants dry in the sun for a week, and then pick off the nuts and let them dry indoors for two more weeks. Many people use movable carts to cure peanuts, so they can be dried outdoors on sunny days, and moved to shelter before forecasted rain.
Peanuts are a relatively good storage crop. Dry, unshelled peanuts will store in a cool, dry place for several months. For long-term storage, shelled raw peanuts can be stored in the freezer.
To save peanuts for replanting, select a number of large, perfect nuts with hard shells. When thoroughly dry, store them in an airtight jar in the refrigerator. Because of their high fat content, peanuts stored at room temperature may lose viability in only one year, but refrigerated seeds will store for up to three years.
For growing advice for many more garden crops, check out our complete Crops at a Glance Guide.
Contributing editor Barbara Pleasant gardens in southwest Virginia, where she grows vegetables, herbs, fruits, flowers and a few lucky chickens. Contact Barbara by visiting her website or finding her on Google+.