A legume that’s not difficult to nut out
Have you ever thought of growing your own peanuts? They certainly would be a fun crop to get your children interested in gardening.
Peanuts are similar to dwarf beans to grow but there is something strange about them. The unusual thing is that after flowering for one day, the flowers bury themselves in the ground where pods develop and the fruits ripen. This process is known as geocarpy.
Peanuts, or groundnuts as they are sometimes known, are grown on a global scale of about 46 million tonnes a year. Our consumption of them as snacks and peanut butter is only a tiny part of the way in which they are used as food.
The peanut is a legume like peas and beans, and like most other legumes their roots have nodules containing symbiotic nitrogen-fixing bacteria. This capacity to fix nitrogen means peanuts require less nitrogencontaining fertiliser and improve soil fertility, making them valuable in crop rotations, particularly in countries where nitrogenous fertilisers are expensive. Like many other legumes, the leaves are closed at night.
Peanuts originated in Argentina and have been selected over thousands of years until we have the plant we know today.
Growing your own peanuts is not too difficult. Seeds can be purchased online. They need to be planted in full sun, in loose, welldrained soil rich in compost, wellrotted manure or other organic matter. The soil must be loose because the pods need to be able to easily bury themselves.
To get peanuts to maturity you need at least four months of frostfree days to reach harvest. Peanuts can be sown in the gar- den three to four weeks after the last frost in spring. Plant the peanuts in double rows to save space, staggering the seeds 30 cm apart. When the plants are 25 cm inches tall, mound earth up around the base of the plant so that faded flowers can burrow down into the hill. The plants are fast, growing anything up to 40 cm tall with yellow, sweet-pea-like, self-pollinating flowers appearing in summer. To develop well, peanuts need warm weather throughout the growing season.
Peanuts prefer regular, even watering. Keep the soil moist until the plants begin to flower, then water less. Once plants are established, allow the soil to dry between waterings. Peanuts will be ready for harvest when the leaves turn yellow and begin to wither, usually four to five months after planting or when frosts start.