Saving Brassica Seeds

I collected seeds from a brassica plant for the first time last weekend.  I am almost certain - hmm, let's say about 90 percent sure - that these seeds are from a bolted bok choy originally planted sometime last fall and overwintered in our weedy side garden.  But if I'm wrong, then they are from a bolted tatsoi plant, also overwintered.  I'm not too worried about not knowing the exact plant variety, because they both grow very similarly in our garden (the typical rosette growing pattern of tatsoi was very difficult to see in my garden last year) and we like the flavor of both. 

This small bagful of seeds came from just a part of one bolted plant, so I now know that if I ever want to collect brassica seeds again, I only need to let one plant bolt and go to seed.  This is already probably way more bok choy seeds than I could possibly plant in one season anyway.

The entire seed collecting process was pretty easy and simple.  The bolted bok choy put out a long flower stalk that bloomed small yellow flowers for a few weeks, and before I knew it, there were seed pods.  The seed pods started out thin and green, then became more swollen, and finally turned brown and dry, as pictured above.  If the pods get too mature/dry, they will split and explode (literally) on their own and scatter their seeds everywhere.  I'm sure I'll see some volunteers growing in this part of the garden later this fall or next year.

I collected the brown seed pods and gently rubbed them between my fingers to get the seeds out of them.  It was a little bit tedious separating out the remaining empty pods (aka chaff) from the collected tiny seeds, but I figured seed saving was worth at least that much effort.  If I had to process a greater quantity of seeds, I might have used a large bowl to collect the pods, but for the relatively small quantity that I collected, this large plastic lid I used was fine.

Although this is the first time that I collected seeds from a bok choy plant, I'm guessing that the process is the same for all brassica plants like Asian greens, cabbage, broccoli, radish, kale, etc.  Right now there are some bolted daikon radishes in my garden and the seed pods on those plants are very plump, almost like pea pods.  I'm curious to see how they will change when they are mature.

Daikon radish seed pods