This herb is described as a popular, spicily aromatic culinary herb that is used fresh in salads and for pickling and flavouring in my The Complete Book of Herbs book. I have to admit to never having heard of the word perilla before today but I have heard of the culinary term shiso! It is a hardy, branched annual which grows to 1.2m with broadly ovate, serrated leaves, which vary in colour from green to red and purple. The leaf edges may be curled while the tiny white to purple flowers are borne in dense spikes about 10cm long.
The varieties include green cumin; purple cumin; aojiso (for use with sashimi), red or akajiso, kleannip or Korean and Thai.
Perilla flourishes in moist well drained soils enriched with compost. Plant seed in spring when the soil has warmed. Pinch out the initial flower spikes to encourage bushy growth. Harvest the leaves in summer and use them fresh or dried. Harvest flower spikes when they are fully developed and the seed in autumn.
The red variety of perilla is more often used for culinary purposes than the green. (Be aware that excessive handling of the leaves can cause dermatitis). A volatile oil in the leaves contains a compound that is 2000 sweeter than sugar and is used as an artificial sweetener in Japan.
information sourced from The Complete Book of Herbs