The fall temperatures have stopped almost all growth on basil plants here in Zone 9 and most of the leaves that remain already have a “woody” flavor. This time of year there are pretty much only 2 options, compost the plant or allow it to bolt to seed.
Historically basil seeds have a poor germination rate, and that will stand true for most seeds that are harvested in the home garden. But on the good side, a decent sized plant can produce MANY seeds, so even a low germination rate can lead to a large amount of seedlings.
Encouraging a basil plant to bolt is very simple, all that is required is sun and water. Continue to care for the plant the same way it has been cared for all year, just do not pinch any new growth off. Allow the flowers to grow! The seeds are ready to harvest once the flower stalks have dried out and the seeds inside have turned to a dark brown.
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