Brassica rapa is a BIENNIAL growing to 0.5 m (1ft 8in). It is hardy to zone (UK) 7 and is not frost tender. It is in flower from May to August, and the seeds ripen from July to September. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees. The plant is self-fertile. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: acid, neutral and basic (alkaline) soils and can grow in very acid and very alkaline soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.
Invasive in Australia, Fiji, New Caledonia, and New Zealand, and can be invasive in the USA.