20-30 days to maturity.Brassica rapa var chinensis. Jimao Choi Hybrid Pak Choi Chinese Cabbage Seeds. Non-GMO, warm or cool-season annual, hybrid. This is a feather-type pak choi and is meant to be harvested young. Plants grow fast (20-30 days) and upright. Leaves are green, oval-long spoon shapes with green petioles. Jimao Choi is tolerant of heat and is excellent for baby leaf production. ~ 5,000 seeds per oz.