Radish Seeds - April Cross - Hybrid. Non-GMO. Raphanus sativus. 60 days. Cool season annual. This giant white radish or daikon is a market leader for its extra-slow bolting habit, tender mature flesh and reliable harvest. The root is all white, 16" long, 2.5" in diameter and weighs around 2 lbs. It has moderate heat and cold tolerance. ~ 1,600 seeds / oz.