Growing Biennials from Seed
What is a Biennial ?
A biennial plant is a flowering plant that takes two years to complete its lifecycle. In the first year, the plant grows leaves, stems, and roots. Over winter it will enter a period of dormancy. The plant will then flower, producing fruit and seeds before it finally dies.
Biennial seeds are generally planted in late summer and early autumn. They can be sown directly into a well prepared seedbed. Or sow indoors in modules cover with glass to prevent them being disturbed and place outside where they can enjoy a period of cold ( known as stratification of the seed) it simply means that the seed is exposed to the cold some seeds will not germinate unless this happens. Keep soil moist. Thin as required, transplant young plants to their final positions the following spring.
You can sow indoors at other times of year. Mix seed with damp vermiculite and place in a polythene bag. Place in a fridge for 4-6 weeks. Remove from fridge and sow into moist well-drained seed compost at 18°C. Germination can take many months, but if germination does not occur repeat cold stratification. Once germinated move to individual pots. Plant out to flowering position once danger of frost has passed in late Spring.