Arachis hypogaea

Arachis hypogaea is a ANNUAL growing to 0.3 m .
It is hardy to zone 8 and is frost tender. The species is hermaphrodite and is pollinated by Insects. The plant is self-fertile.
It can fix Nitrogen.
Suitable for: light , medium and heavy soils and prefers well-drained soil. Suitable pH: acid, neutral and basic soils and can grow in very acid and very alkaline soils.
It cannot grow in the shade. It prefers moist soil.

Prefers a light humus-rich well-drained soil in a warm sunny sheltered position, though it will tolerate heavier soils. Plants prefer hot dry conditions when the crop is ripening. Peanuts are quite tolerant of acid soils, and aluminium, requiring a minimum of lime for acceptable yields. Tolerates a pH in the range 4.3 to 8.7. Plants are not frost-hardy and most cultivars require too long a growing season to make them a viable crop in Britain. Some cultivars, however , have a shorter growing season and are worthy of more research in this country. The peanut is widely cultivated in the tropics and sub-tropics for its edible seed and oil contained in the seed, there are many named varieties. It grows best between latitudes 40° south and 40° north. Yields average about 1 tonne of unshelled nuts per hectare, about 80% of this weight is edible seeds and 60 - 75% . Crops can be grown at further distances from the equator but yields are likely to be poor. There are three main groups of cultivars:- 'Virginia' has large seeds, 'Valencia' has four seeds per pod and 'Spanish' has the smallest seeds. There are running and erect forms in each group. The erect forms mature more quickly and are therefore more likely to succeed in colder areas. 'Early Spanish' matures in 105 days and has cropped reliably as far north as Canada. 'Spanish' matures in 110 days and crops in Canada if grown in a light sandy soil with southern exposure. Plants are, in general, self-pollinating, though occasional outcrossing by bees occurs. This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby. When removing plant remains at the end of the growing season, it is best to only remove the aerial parts of the plant, leaving the roots in the ground to decay and release their nitrogen.