Spinach Seeds - Chinese - Green Arrow - Hybrid -3 g Packet ~270 Seeds - Spinacea oleracea Non-GMO -- F1 Hybrid -- Open Pollinated -- Asian Variety -- High Germination Rate Seeds For: Vegetable Gardening Days to Full Maturity: 40-60 -- Annual -- USDA Hardiness Zone: Annual Crop, Not Intended To Overwinter Kitazawa Seed Company Brand - Premium Quality Asian Variety Garden Seeds & More - Since 1917 Spinach Seeds - Chinese - Green Arrow - Hybrid. Annual. Spinacea oleracea. Asian Type. Non GMO. Open pollinated. 40 to 60 days to maturity. Pointed Leaves in a dark green color. Slow bolting, cold and heat tolerant. Light pink root. Resistant to DM race 1-11, 14,15. Can be sowed in spring, summer and fall seasons. Spinach is a cool weather crop. Seeds prefer to germinate in cold weather. Optimal soil temperature for emergence is 10~18 °C/50~65°F. It can be planted when soil is workable in spring. Higher soil temperature ( over 20°C/68°F) may result in sharp decrease in germination rate. Seeding in summer is not recommended. Spinach tends to bolt (seed-stalk development and flowering ) as day length, temperature and plant density increase. Water stress and inadequate nutrients increase bolting risk. Exposure of young plants to low temperature (4°C/40°F ) also increases the risk of bolting. Apx. 2500 seeds per ounce.