How to save Basil Seeds
Allow your basil plants to flower, and the flowers to turn brown.
Carefully cut the seed heads (the brown part) from the plant.
Place the seed heads in a paper bag and hang the bag upside down in a dry, well-ventilated area.
After about two weeks, the seed heads will become brittle. Shake them to release the tiny black seeds.
Collect the seeds and store them in a labeled paper envelope or small glass jar in a cool, dark place.