I'm wanting to get some peanut seeds to plant. However, I'm thinking about saving some that I buy now for next year (as well as harvesting my own to save). How long do the seeds generally stay viable?
Short question, short answer. Peanuts when harvested and stored properly can retain viability up to 3 years frozen, 1 year at room temperature. Longer viability correlates with low moisture content, as well. The viability will be enhanced if the seeds are stored in the pods, or treated with fungicide.
For further reading, check out this article from Purdue (specifically item J, under category V.).