Seeds may be easily collected from many annuals and biennials for sowing the following year; the secret of success is to collect the seed at the right time and to store it correctly. However, it is often only worth saving seeds from those plants that stay true to type, such as honesty or Nigella, as seeds saved from many garden-grown cultivars will not produce plants that demonstrate the same habit or flower characteristics as those of their parents.

Collecting

After flowering has faded, the seed heads will form, ripen, then the seeds will be dispersed. To collect the seeds, you will need to wait until the seed is ripe, but before it is dispersed. Seeds should always be collected on a dry day as damp seed will rot when stored.

Drying

When seed capsules turn brown and begin to split, cut them off and take them indoors. Put a clean sheet of paper on a tray and use your fingers to remove the seeds from the surrounding petals. Spread the seeds across the trays and leave them in a warm, sunny place until they are fully dry.

Storing

After they are dry, extract the seeds and clean away any surrounding debris, either by using a sieve or by gently blowing the chaff away with a drinking straw.

Store the clean, dry seeds in an airtight container such as an empty film canister, along with a sachet of silica gel to keep them dry. After labelling, keep the containers in a cool place until they are required for sowing.