Radish Seeds - Minowase Summer Cross #3 - Hybrid. Non-GMO. Raphanus sativus. 55-60 days. Annual. This popular Japanese hybrid radish (daikon) has a long, white tapered root that is mildly pungent. They can reach 16" long and weigh 1.75 lbs. It is the finest radish variety for summer to fall harvest with good heat tolerance. ~ 3,500 seeds / oz.