30-40 to maturity. Brassica rapa var. perviridis. Senposai Komatsuna Mustard Seeds. Non-GMO, warm or cold-season, annual, hybrid. This popular traditional Japanese komatsuna hybrid has glossy, thick dark green leaves and an upright growing habit. Senposai Komatsuna is known for its vigor, healthiness, and hardiness. This unique vegetable has the sweet taste of cabbage and the tenderness of komatsuna. Komatsuna is extremely underrated in the west. Senposai is heat tolerant and grows well all year round though it prefers mild temperatures. Also ideal for sprouts. Approx 9500 seeds / oz.