(Brassica napus) (aka Ragged Jack) One of the hardiest and most tender-leaved of all kales, this variety is originally from Siberia and was brought to Canada by Russian traders around 1885. Its beautiful, frilly, purple-veined, blue-green leaves are tinged with red-purple and resemble oak leaves. Vigorous plants grow 18-36" tall. Leaves have a mild, sweet flavor. Hardy to -10°F. 50-60 days from transplant.