Peanuts, a cultivated crop that dates back as far as 7,000 years ago according to Peruvian records, are unique in that they flower above ground but ripen their fruit in pods below ground. This neat fact is reflected in their botanical species name hypogaea - hypo (below) gaea (earth.) Cheery yellow flowers produce pegs that extend to bury themselves in the soil surrounding the plant's central taproot. Thanks to the extensive work of early 20th century African American agronomist George Washington Carver peanuts now enjoy a ubiquitous presence in households across the globe.
Keep peanuts in their outer shell until ready to sow. Direct seed peanuts when the soil temperature is consistently above 65°F. Remove nuts from their shell carefully to avoid damaging their thin inner colored skin. We space our peanuts 6-8 inches apart within a row with 9 inches between rows.
Peanuts fix their own nitrogen so avoid over-fertilizing with nitrogen which will promote leaf growth over flowering and peg setting.
Plants are frost sensitive so we covered ours during an early frost mid-September. We usually harvest the plants whole early October by gently lifting them with a potato fork. The leaves are only just beginning to yellow, but concern over loss due to critter pilferage and/or rotting in the cooler, moist October soil leads to a "better safe than sorry" approach. Plants are hung in a warm well-ventilated barn to dry down. Some people wash the pods while still on the plant before hanging them but with just 30 hours in the day we don't
Peanut flowers are self pollinating. To save true-to-type peanut seed, use an isolation distance of 10-20 feet between different peanut varieties*. To maintain a strong gene pool, collect seeds from as many healthy plants as possible, the more the better. Peanut seeds maintain their viability best when kept in their pods until ready to plant.
For Valencia type, a count of 100 shelled seeds, ready to plant, weigh around 46 grams.
* Seedsavers Exchange 2017