Picture taken today. Temps are around 0 degrees celcius and somewhat to my surprise, the leaves of this plant perked up. You can see some frost scorch on them nonetheless.
"If you thought that weeks of weather with lows in the minus double digits and wind chills causing a vertigo inducing dip below that, ice storms that coated me in several inches of ice, and weeks with no sun could kill me, then you were WRONG!"
-- says 'Red Cavalier' kale
This is one of a gang of possibly 'perennial' or long lived brassicas that are undergoing winter - Ottawa style - to see who emerges on the other side of the spring melt alive. Of course, just because a plant survives one winter (or half way through one winter) doesn't mean that it is hardy around here. It may mean that we had lots of coozy snow to protect its root system or that we had particularly mild temperatures. A killing year is one with less than average snow fall and lots of cold snaps. So far, I would say that this winter has been average.
Some oldsters who have survived several years are:
Very hard kales like Red Ursa and Dwarf Scotch Curled
This one is 'Red Ursa' kale, a nice cross between Red Russian and White Ursa if memory serves correctly.
This is the species, I think. I also have the cultivar 'Lily White.'
Horseradish: I love the vegetable which is good because it's here to stay.
Got the first root from the grocery store, but if you don't feel like spending the couple bucks, contact me in the spring. I have roots for you (as do I supsect anyone else who has grown it before does.)
Upland Cress (Barbarea vulgaris): No picture sorry. I want to try variegated winter cress but it is not supposed to be hardy here. The regular all green variety, on the other hand, is hardier. It may also self sow.
Some others undergoing the 'test'
Walking kale / Chou Daubenton
The one not beheaded by the rabbit. I have a couple others undercover.
9 star broccoli (cauliflower): I don't expect this one to make it.
I've heard not to expect too much from this sprouting 'cauliflower' - seen here as the wavy grey/green leaves next to my youngest. Next year, I am growing it in a polytunnel as well.
Thoughts on brassica suvival:
Chinese heading cabbage resprouting from the crown. This died shortly afterwards I believe.
Large leaves and heads tend to die back, especially if they are above the snow line. I have had some cabbage heads, particularly 'Red Rock Mammoth', overwinter but most of the wrapper leaves were dead. The stem with cabbage and brassica sometimes manages to resprout a head and some leaves and then go on to flower. Plants that resprout from the roots also do better like Seakale. Short open leafed kales can also make it. Of course annuals that reseed such as mustards have carpetted my gardens with babies in the spring.
In warmer climes, many brassicas such as purple sprouting broccoli and overwintering cauliflower all sail through winter to produce crops in the spring. Sources say that they have seen kale that is tree like in proportions in some very mild areas.
More on perennial or long lived edible Brassicas