Vigna angularis

Cultivation Details

Adzuki bean is a plant of the subtropics, and is widely cultivated from the temperate zone to higher elevations in the tropics, where it is can be grown at elevations from 420 - 1,500 metres. It grows best in areas where annual daytime temperatures are within the range 15 - 30°c, but can tolerate 5 - 36°c^[1]. The plant cannot tolerate frost. It prefers a mean annual rainfall in the range 900 - 1,300mm, but tolerates 530 - 1,800mm^[1]. It is generally seen as a short-day plant, requiring a day length of 12½ hours or less to initiate flowering and fruiting, though cultivars can vary in their response to day length^[2]. Requires a sunny position^[1]. Succeeds in a wide range of well-drained soils^[1]. Prefers a pH in the range 5.5 - 6.5, tolerating 5 - 7.5^[1]. Some cultivars are fairly drought tolerant^[2]. The plant can commence cropping within 60 - 190 days from seed^[1]. Average seed yields range from 1 - 2.5 tonnes per hectare. In Taiwan yields of 1,450 kilos are common, in Japan 1,900 kilos, in Kenya 500 - 600 kilos and in New Zealand 1,340 - 2,240 kilos^[1]. There are many named varieties^[3]. 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^[2]. 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.