British Columbia: never ending cauliflower

Several years back, I bought some cauliflower plants and put them out in the garden. They did not do much, but I left them in and they surprised me with a better head the next year. This must be their 4th year in the raised bed and I had beautiful 8" heads this year! They stand about a 20" now and when they get too leggy, I will take the occasional one out. They also make little plants off the stem which grow easily by just pushing them in the dirt. We have a sunny site and do not experience super cold temperatures. So are brassicas actually perrenials? Has anyone else had this experience? Have also left cabbage in with new ones coming.

 

Can I ask how many years they produced for? Did you cut the plant back during the winter/after harvest? I am very interested in this, I thought they were annuals!! I have both cauliflower (and broccoli), and red cabbage.
Thanks for the info!

 

The original wild version of Brassica oleracea is a bienniel, but the plant has changed a lot while being developed into all of its horticultural varieties. It's quite common for these plants to continue growing after the flower head has been removed, especially in a mild winter zone like the coastal Pacific Northwest. I see a lot of overwintered Brassicas in my Burnaby neighborhood, but I prefer to rotate them every year to avoid encouraging diseases like clubroot.