We have kale (common curly, red russian/purple, redbor and lacinato/black/tuscan/dino), chard (perpetual spinach and rhubarb supreme), collard greens and mustard greens at the balcony.
Canaries can eat like this all the year from your plants. They eat the leaves, the pods:
the dried seed pod as well (where they also play with it, carry it around for example):
and the seeds from the plants:
There are salads like kale and the perpetual spinach, that can survive snow as well, so even it norhtern countries, where snow is present every year, you get to give salad to your birds all year around.
Bibliography:
Yannis and Stella @Apollon, Naxos 