Smartweed is a water plant, growing in shallow water or wet soils with spicy young leaves. Originally from Asia.
Water Pepper has a long history of herbal use, both in Eastern and Western herbalism. It is not used very often, and is seen more as a domestic remedy being valued especially for its astringent properties which makes it useful in treating bleeding, skin problems, diarrhoea etc.
Sow spring in a pot standing in water or in situ. Germination is usually free and easy. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in the summer if they have reached sufficient size. If not, overwinter them in a cold frame and plant them out the following spring after the last expected frosts.
Succeeds in most soils if they are wet and dislikes shade. Germination can be erratic.
Leaves and stems - raw or cooked. They can also be made into an acid peppery condiment. They are very hot.
Seed - raw or cooked. It is rather small and fiddly to utilize. The seed is used as a condiment - a pepper substitute.
The sprouted seeds or young seedlings can be used as a garnish or added to salads, they are commonly sold in Japanese markets. They are very hot.