Red shiso is a variety of shiso and plays an important role in Japanese cuisine and food culture. Like green shiso, this plant was probably introduced to Japan from China 1,000–2,000 years ago, where it has become an indispensable ingredient.
Unlike the green variety, red shiso has deep purplish-red leaves and an intense flavour: spicy, slightly bitter and with notes of cinnamon, aniseed and mint. This powerful flavour makes the herb less suitable as a neutral garnish, but ideal for adding flavour and colour. Red shiso is traditionally used in the making of umeboshi (pickled plums) to which it lends both flavour and its characteristic red colour. It is also used in syrups, vinegars and drinks. The leaves however and can be used for pickling all kinds fruits and vegetables and afterwards the leaves can be dried and ground into a flavourful topping! Usually, the leaves are too bitter to use fresh. As with green shiso, the flower buds and flowers (hojiso) are also edible and suitable as a garnish.
The plant is native to a subtropical climate and can be grown in temperate regions as an annual in the garden or as a houseplant. In southern Europe, the species can naturalise locally, so some caution is advised. However, the species does not appear to be invasive in the Netherlands, as is the case, for example, in the US due to the longer growing season. If you plant the species in a garden in southern Europe, it is best to pick (and eat) the flowers to prevent seed formation. The leaves can be harvested after just a few months. Depending on the amount of leaves harvested, the plant can grow to a height of 60–90 cm and then produce small purple flowers. If the main stem is pruned, the plant produces more side stems and thus more edible leaves. The plant grows best in full sun and is somewhat drought-tolerant.
Sowing description: Sow the seeds in sowing mix and keep the soil constantly slightly moist. Allow to germinate at 20-25grC. Germination usually occurs after a few weeks. If the seeds do not germinate, they can possibly be placed in the fridge and then put back in a warm place. This could help break potential dormancy.
