Radish Seeds

the many benefits of growing radishes

Radishes get their scientific name, Raphanus sativus, from the Greek word (raphanus) meaning “quickly appearing.” This is no exaggeration as certain varieties go from seed to munchable in as little as 25 days! Originally cultivated in Southeastern Asia, radishes date back to 2700 B.C. Ancient Egyptians were even fond of radishes, using their seeds as a source of oil before olive trees were introduced. Radish seeds made their way to Europe in the 1500s and to the US by the 1600s. Radish Greens are also edible although they tend to become spiny as they age and are less popular than the root. Radish roots make crisp peppery additions to salads and veggie trays. Radish seeds also make an excellent quick crop of microgreens.

How to sow radish seeds for the best results

Radishes are a close cousin of kale, broccoli, and cauliflower, all found Brassicaceae family. Annual in zones 3 to 10, radish seeds can be sown directly in the garden in the spring or the fall. They prefer cold temperatures and may bolt/go to seed when weather becomes too hot. Seeds typically only take between three to five days to germinate. Keep soil moist after seeding to ensure even germination. Consider succession planting quickly-maturing varieties, seeding every 15 to 20 days for a continuous crop. Take note that some varieties, including Black Spanish Radish Seeds and Watermelon Radish Seeds, need to be planted after the summer solstice in northern regions because they are sensitive to day length and require shorter days to “bulb up” and mature.

Soil and light conditions for your radish crop

Radishes prefer full sun to partial shade for optimal growth and welcome increased shade during warmer months to keep them cool. They do best in rich soils, although nutrient needs are minimal because of how quickly they mature. Amend soil with a mild fertilizer or compost prior to and between plantings. Radishes can be grown in containers and are great for planting on a sunny balcony or patio. Optimal spacing is two to three inches, depending on the variety. Make sure to thin crops that are too thick before roots begin to form, about 10 days after planting.

Radishes are sometimes susceptible to wire worms and root maggots and do best in spaces where soil has already been worked. Adding a floating row cover can prevent these pests from laying their eggs and reaching your radishes. It can also extend your growing season by two to three weeks in both spring (earlier planting) and late fall (later planting).

For more information about planting, growing, and caring for radish seeds, see the Radish Seeds Planting Guide.