Many biennial plants grow from year to year in the same spot and are wrongly assumed to be perennials (which actually DO live for several years). But plants such as Foxgloves – seemingly endless for those lucky enough to have a drift – which will populate the same area for many years, simply survive as biennials – not perennials – as will many others; the humble Forget Me Not included.
Most true biennials will die out if you persist in deadheading the blooms and thus prevent the plants from setting and scattering their seeds.
Self seeding plants of the biennial group normally produce seeds directly after or during the flowering season. The seeds normally drop to the ground or are scattered nearby. This nearby ‘seeding’ is a cleverly thought out action plan for survival, for the seeds will be ‘sown’ in conditions which are suitable for survival – hence the parent’s satisfaction with the area!
The newly produced seeds normally germinate and produce small new plants during late summer or autumn. These then over-winter in-situ and then grow and flower the following year, resulting in a continuous display of plants for many years to follow.
Sow seeds in seedbed outside in summer.
Transplant the seedlings in autumn or the following spring, in the place where you want them to flower.
After flowering - in following autumn – they are dug up, and put on the compost heap.
Many biennials will re-seed themselves year after year, without you needing to interfere.
Examples of self-seeding biennials are Forget-me-nots (Myosotis), Honesty (Lunaria), Poppies (Papaver), Foxgloves (Digitalis) Californian Poppies (Eschscholzia).
After your plants have flowered, be careful not to ‘weed’ out the new plants which will soon grow. They are next year’s flowering display