Shiso (Perilla frutescens) is a Japanese herb from the mint family, it is known by several other names including perilla, beefsteak plant, Chinese basil and purple mint. There are three variations of colour: green, red/purple and bi-colour (green and purple). Each adds spectacular brightness to a garden and they look most impressive grown together in an ornamental bed or at the end of a row in the vegetable patch.
Leaves and flowers of all shiso plants are edible and have a flavour that is likened to mint with an earthy depth and hints of basil, cumin, cinnamon, and anise. Leaves can be chopped and tossed into salads in place of basil or mint, and added to soups, stir-fries, and casseroles or as the quintessential garnish to plates of sushi and sashimi. The purple leaf is lighter in flavour and is traditionally used for its colour, most famously to add the distinctive purple to ume fruit in umeboshi, a staple of Japanese cooking. Tiny, edible flowers of all colour plants emerge in late summer and these make exquisite decorations and add a surprising burst of characteristic herbal flavour to fish and vegetable dishes and look fantastic as toppings to ice cream, sorbet and other desserts. When the flowers start to turn to seed the buds can be picked and added to soy sauce for an original, fragrant dip for sushi and sashimi.
Although perennial in some Asian climates shiso is an annual, non-hardy plant in the UK growing fast in late spring, rapidly building height and throwing out abundant leaves, it passes to flower in late summer before dying with the first frost. Capable of reaching heights of over 1m shiso will remain low and bushy if growing tips are pruned in the same way fresh mint is harvested.
Growing shiso is straightforward and rewarding with impressive yields produced in quick time. If you can grow basil you can grow shiso as the requirements are the same. In the garden plant into free-draining, moist soil once all risk of frost has passed, aim for exposure to full or partial sun. In a pot use standard compost and if available, mix in composted bark. Mulch will help in both scenarios, as leaves are more succulent when the soil is kept moist. Harvest leaves, growing tips and flowers throughout the season. The more growing tips you pinch out the bushier your plant will remain.
Please be aware shiso plants will not survive frost. Please harden plants off and plant out when risk of frost has passed. More detail below.
Remove and dry all leaves before the first frost and store for adding to sauces, soups and stews like any other herb. Leaves, either dried or fresh, make an excellent tea. The tea made from purple and bi-colour leaves starts blue before turning dark purple as the colour seeps into the hot water. For an iced tea, pour from the pot over ice and add a dash of lemon or yuzu juice to turn the tea bright pink and wonderfully refreshing.
Shiso is a great source of calcium, potassium, iron, vitamins A, B2 and C and is rich in Omega-3 fatty acids and rosmarinic acid, which has powerful anti-inflammatory properties, making them a healthy choice for humans. Shiso leaves are however toxic to cows and other livestock and although they will usually avoid them please cultivate shiso where they cannot be reached by these animals.
