I am also looking for perennial brassicas. If I find them I will make sure to update this
thread. Daley's had some but all have been OOS for me for months. -_- Many of the garden centres have explained that with the pandemic people who know nothing about growing or caring for plants are buying everything they can get their hands on. Out of season or whatever, then asking for refunds on soon dead plants. It is good that interest in
gardening is rising. I just hope not too many poor plants die in the process. -_- Please let me know if you find a source too, it would be very greatly appreciated. When I get time, I will write a list of the perennial vegetables I have and what I am looking for. I had one for my farm in Missouri and it always proved most helpful.
One of my roommates accidentally whipper snippered my sweet leaf katuk and a banana plant, so I am finding it best to try to have more than one if you have the room. Unfortunately here I do not. -_- But I will do my very best to keep this list up to date and I will check out the places you mentioned. Thanks!