Hi Have any of you tried saving seed from this? Mine is in the tunnel so I think little chance of crossing with other brassica? However I’m unsure how to tell when it is ripe enough to harvest the seed? Presumably just before the pods are dried and then finish drying off elsewhere in order to prevent rampant self seeding?
I have tried similar with poor results because brassicas need to cross pollinate with 6-10 others to widen the gene pool. See http://www.realseeds.co.uk/seedsavinginfo.html for excellent info.
Seed saving is not all straightforward and for some veg you need a lot of space!
Yes worth a try is you have a dozen, I would pull the plants when about half the seed-pods are dry and brown, then hang in an airy place for 2-4 weeks, then lay on a sheet on concrete and walk on the plants to break the pods, etc.