How to grow woad (Isatis tinctoria) for indigo for dyeing.
- Sow seed between March and May, In full sun in a loam/clay soil.
- Sow the seeds in rows about 40cm/15in apart. About 1 seed every 10cm/6in at a fairly shallow depth and cover with about 1cm/1/2in of soil.
- Seedlings are prone to slug and snail damage. Later in the year they are susceptible to the cabbage white butterfly as they are brassicas.
- Weed regularly, as you have to be careful that the weeds don’t choke the seedlings.
- Water when necessary, if weather is dry.
- From end of July you can cut the leaves to extract the indigo.