Growing and Saving the Seed Of Radishes

Whether grown for a small, piquant pop of color in a spring salad or for a mellow and meaty winter root vegetable for cooking, these easy-to-grow, highly nutritious root veggies can’t be beat. They can also be used for soil improvement! 





Radishes are believed to be native to Southeast Asia. They were first mentioned by the ancient Greeks in the 3rd century B.C. In 1544, a German botanist reported seeing radishes over 100 pounds. Radishes were one of the first crops that European brought to the New World. 


  • Culinary




  • Radishes like rich, well-drained soil and plenty of moisture.
  • Amend beds with compost, and sow seeds 1⁄4 to 1⁄2 inch deep.
  • Direct sow spring radishes starting 4 weeks before the last frost date. You can succession plant every two weeks for the quick-growing varieties like French Breakfast or Purple Plum.
  • Sow winter radishes in late summer, about 2 months before the expected first frost. Direct sow and thin to 4-6 inches apart, for the roots need plenty of room to make a good bulb. 
  • Days to germination vary a bit by type of radish but typically range from 3 to 10 days.

  • Ideal germination temperature is 50-75 F.




  • There are two main types of radishes: spring types and winter types. Spring radishes are small and quick growing; they can be harvested in as few as 3 weeks!
  • Winter radishes take longer to grow, but they can be stored for up to 6 months.
  • Radishes are a cool-weather crop and will grow best in spring and fall, but they can be grown throughout the summer except in the hottest parts of the country.
  • Spring radishes are often interplanted with carrots or parsnips. The radishes will germinate and mature well before their planting partners, which need just about a spring radish distance between their roots. Harvest the radishes within 30 days and let the other root crops continue growing.


  • Radishes’ most common issues are related to heat and water. Radishes do not like excessive heat. It will hinder root formation or cause woody roots, and the plants will go directly to seed.
  • Inconsistent watering will cause cracks and splits in the roots.
  • Low sunlight will cause slender roots that do not bulb up. 
  • Do not plant during the heat of summer; radishes much prefer spring and fall. 




  • Radishes are insect-pollinated, so you’ll need to isolate varieties by up to 1⁄2 mile or stagger plantings to avoid flowering at the same time.
  • Staggering can be easy because of the radish’s quick maturity.
  • Allow flower stalks to shoot up and seed pods to dry on the plant before picking pods and opening by hand.
  • Seeds will remain viable for up to 5 years when stored in an airtight container.