Though it may be inevitable in today’s food-trend-centric market to avoid that hardy, chewy, dark leafy green known as kale, there are so many varieties that it’s likely you have not seen them all. Red Russian kale, also known as Ragged Jack kale, is an heirloom variety thought to have been brought to Canada from Siberia by Russian traders circa 1885. Like most varieties of kale, it’s a hardy, green plant. Unlike other varieties of kale, it has a purple stem and wispy, oak-like leaves—that happen to turn purple, and get sweeter, in cold weather.