A less expensive production method is semi-protected planting. Seedlings are grown in heated beds in a plastic house in late winter, transplanted in spring and harvested during summer. Using this method, plants are protected from wind and rain when growing conditions are marginal. However, without artificial lighting, plants quickly bolt to flower and seed in autumn. The least expensive production method involves seedling production in unheated beds in early spring followed by transplanting in late spring.
Harvesting is carried out during the summer months.
Bundles of 10 leaves are tied with a rubber band and packaged ready for market. Harvesting, which is labour-intensive and a major cost to the grower, should be carried out at least once every two days and more often if plants are growing rapidly. Red perilla Red perilla, which is not usually produced out of season, is grown as a bulk commodity and used in Japan mainly by the processing industry. It is sown, in spring, directly into raised beds that have first been fertilised and cultivated. Five to six seeds are sown per station in 80 cm wide raised beds.