50-60 Days to Maturity.Cucumis sativus Progress Japanese Cucumber Seeds F1. Hybrid. Non-GMO. Annual. Non-GMO. This Japanese cucumber has glossy, green, smooth skin and is crisp and very tasty. This is an excellent early producer that will provide beautiful, straight fruit that grow up to eight inches in length. This is a vigorous and high yielding plant that is heat tolerant and disease resistant.