Peanuts (Arachis hypogaea) aren't true nut plants but are actually an annual legume. They're prized for their underground seeds, which are enjoyed as a raw, boiled or roasted snack. Improper harvesting, poor timing and inadequate post-harvesting treatment could ruin your peanut crop. Do it right, and you'll be treated to pounds and pounds of the tasty seeds, which are called peanuts.
Peanut Growth and Harvest Preparation
Write down the date when the peanut plants first germinate. It takes the plants about 120 days from germination to mature for harvesting. The plants sprout their first flowers 30 to 40 days after breaking through soil, and the journey that each flower follows from blossoming to peanut pod is what makes this plant such an unusual specimen in the garden. After a peanut plant flower is pollinated, the stalk, or peg, beneath its ovary becomes longer and droops toward the ground. The peg reaches the soil and begins to dive into it. One week after the peg submerges in the ground, its end turns into a seedpod. Nine to 10 more weeks pass before the seeds within the pod are ready for harvesting.
Peanut Plant Test
Once the peanut plants have turned yellow, pick one or two of the plants to test for harvest readiness before digging up an entire row of peanut plants.
Pull on a pair of garden gloves. Insert a garden fork or garden spade into the soil 12 to 18 inches from a peanut plant's base. Work the tool back and forth, loosening the soil around the plant's roots.
Pull and lift the plant out of the soil.
Break a few seedpods off the plant. Break open one pod. If the peanuts inside the pod are mature and ready for harvesting, then the pod's interior should have dark veins.
Inspect the peanut kernels in the sample pod. When mature, individual peanut kernels have papery, thin skin, and the kernels fill the pod completely. If they're small and rattle loosely in the pod, then the peanuts are not yet mature and the plants may need one to two more weeks before you repeat the harvest test.
Harvest and Post-Harvest Techniques
Harvesting peanut plants is fairly straightforward. Simply loosen the soil around each plant with a garden fork, lift the plant out of the ground and shake the plant to dislodge clumps of soil.
After uprooting peanut plants, lay them upside down in a warm, dry, shady area with lots of air circulation. This location could be a garage, a garden shed or a similarly sheltered spot. Alternatively, tie the plants into a bundle and hang them from a ceiling. Allow the peanut plants to dry for two to three weeks.
After three weeks, the plants should be fully dry and crumble easily when you touch them. At that point, the pods are cured. Pluck the pods off the plants by hand, and store them in breathable mesh or paper bags.