Cabbage Seeds - Pak Choi - Chun Mei - Hybrid. Annual. Brassica rapa Chinensis group. 45-50 days to maturity. NonGMO. Cool-warm season. Chun Mei hybrid is very slow bolting standard large size shangai pak choi. It stands upright and leaves are dark green with broad, long and shiny green petioles. Cold and some heat tolerance and can be planted in spring and fall. ~ 9,750 seeds per oz.