I let a lot of plants bolt in the garden. Plants bolt when they are ready to produce seeds. They will develop a flowering stem and if left alone will often develop viable seeds.
Gardeners often try to discourage bolting. We want leafy greens, not seeds. Bolting stems are often cut away. Plants are planted in cooler temperatures to reduce bolting and bolted plants are often removed.
However, there are many instances when allowing bolting is a good thing. Free seed, and lots of it, being the biggest advantage.
Here is cilantro I let bolt last fall. I let the seeds drop in the same patch. This year we have a great stand of cilantro that is constantly putting out new plants This flowering kale was planted last year and left to bolt. In addition to giving us thousands of free seed, the flowers are great pollinator attractors.A lot of seed saving can be easy, and letting plants bolt is about as easy as it gets.