Growing Peanuts in your greenhouse is an excellent way to get children interested. Pea, Ground or Monkey nuts are known to kids everywhere, if not as fresh nuts then roasted salted ones and certainly their famous butter. Actually Arachis hypogaea is not a nut from a tree but a member of the Pea family, somewhat resembling clover with yellow flowers.
Now Peanuts have an unusual habit that make them especially interesting. As the flowers fade their stems elongate and arch over pushing their seed-pods into the soil where they swell and ripen. It’s really quite captivating to observe this as it happens over a few days.
Once thought Asian or African the Peanut is originally from S. America. Thus needing really warm conditions Peanuts cannot be grown successfully outdoors here in the UK, so proper seeds are seldom offered. Peanuts sold for bird food are a potential source though often damage or stale so those sold for our consumption are much better. Nets of fresh peanuts in their husks are sold, most widely around Christmas. These will be fine as fresh Peanuts can remain viable up to a year if kept dry in their papery husks.
There are two seeds/nuts in each husky pod. In late spring to early summer sow two seeds or better (less inclined to rot) just the whole pods singly in small pots, preferably in a warm propagator, if both seedlings emerge then thin to the stronger.
These are not difficult subjects for other than hating cold and waterlogging they’re almost bombproof. The plants grow rapidly, once moved up to larger pots they become pleasing additions to the greenhouse with attractive mounds of verdant foliage (better in warmer summers).
Because of their odd cropping habit these are best grown in an indoor border, if available. The alternative is wider not deeper pots. They need to be wide enough so once the plants flower the seedpods can be pushed down into the compost. You can carefully investigate to disclose some of these from late summer otherwise harvest in autumn as the plant dies back. They need careful thorough drying to keep so are better eaten straight away.
Do remember that sadly a few folk are seriously allergic to Peanuts, however that is when consumed. The plant itself is generally innocuous (though the foliage, as with many leguminous plants, is NOT edible).