The following is Chad's account of how he grows peanuts in his home garden in Addison, VT.
I bought my seeds from Baker Heirloom Seeds; I did one pack of White Spanish Pearl
--------A small shelled variety that contains 2 good sized nuts. The kernels are wrapped in white wrappers. Was believed to be donated to the USDA by Israel in 1964. They are rare and often sold out so make sure to order really early.
I planted my seeds (Shell and all) in the first week of June to avoid all chances of a frost and give the soil a chance to heat up to avoid any rot. I planted a 5' wide by 10' long bed with two rows (~24" between rows) and a seed every 6" in that row. They recommend 12" spacing and I was going to thin to that, however, the peanuts seemed to be doing fine in a little less space because in our climate they don't get nearly as big as they do down south.
Three weeks in I had great germination and roughly 3-4inches of growth on all my plants and then overnight the rabbits decimated my patch. They took nearly everything down to the ground in 12 hours. I then placed a 4' tall chicken wire fence around them with the base anchored down with landscape staples. This worked great, and I left it up until harvest.
The plants were flowering by Early July and began to set their fruiting pegs by end of July.
Most people don't know, but Peanuts flower above ground like most other plants in the Fabacea family, however, once the flower is pollinated it grows a thick, dark stem like growth called a peg that grows straight down into the surrounding soil where the peanut develops. It takes roughly 2 weeks from pollination for the peg to hit the soil. It takes roughly another 10 weeks for the peg to develop a mature peanut.
Therefore, once you see the first round of flowers you should start to cultivate and loosen the soil surrounding the plants. This will help by allowing the pegs to penetrate the soil much easier especially in our typically clay soils. I personally cultivated the soil at first sight of flowers and then lightly cultivated and mounded the soil once I saw the pegs just starting to touch the soil. I didn't do anymore cultivation after that for fear of disrupting the already established pegs.
I didn't do any type of fertilizer, or any supplemental watering and my plants did great.
The plants starting to turn a light yellow as the first few light frosts hit in early to mid October. At this point I began to pull up a couple pegs to determine how far along the developing peanuts really were. On October 20th I harvested everything. From Seed to Harvest it took roughly 20 weeks. From first Flower to Harvest it took roughly 12 weeks.
For Harvest you simple lift the whole plant with a garden fork, spray the peanuts clean, hang dry on the plant for 2 weeks (the peanut should start to rattle inside the shell), dry off the plant for another two weeks, and then roast or boil and EAT!