How to plant and grow Radishes

Radishes have been grown and eaten for thousands of years. They were domesticated in the Mediterranean, cultivated by the Egyptians nearly 5000 years ago, and introduced to Britain by the Romans nearly 2000 years ago. 

Their hot, peppery flavour is popular across all cultures but another reason for their ubiquity is that they are probably the easiest of all vegetables to grow. Just sprinkle the seed thinly in a shallow drill 1cm (½in) deep and they will appear within a week or so and be ready to start harvesting a few weeks later. It is important to thin them so that they are at least 2.5cm (1in) apart to allow each root to become juicy and swollen before they get woody. The thinnings can be eaten, leaves, roots and all, when they are the size of peas, although the perfect size for a radish is the circumference of a twopenny piece. Fresh radishes in early May, eaten with salted butter, are one of the seasonal treats of spring. 

They will run to seed in warm or very dry weather so sow as soon as the soil is warm enough in spring and make a repeat sowing every two weeks thereafter. Water regularly, but too much moisture will only result in extra foliage and split roots. Radishes are also a very useful indicator crop. I sow mine in with parsnips, on the ridge of potatoes and between slowgrowing crops like cabbages. 

Radishes are a brassica and are prone to flea beetle attack which leaves holes in the leaves and weakens the plant, making it more likely to bolt. To minimise this, keep them very well watered, thin to 2.5cm (1in) spacing between each plant and pull them to eat whilst they are marble-sized. My favourite varieties: ‘Cherry Belle’, ‘Saxa’, ‘Scarlet Globe’, ‘Flamboyant’ (long) and ‘French Breakfast’

Family	Brassicaceae
Growing zones	N/A
Growing season(s)	cool weather: spring and fall
Spacing	2 to 4 inches
Start indoors or direct sow	direct sow
Indoor sowing date	N/A
Earliest outdoor planting	6 weeks before average last frost
Soil temperature	45° to 90°
Fall planting	4 weeks before average first frost
Sun needs	4+ hours
Water needs	low
Harvest category	one harvest
Fun Fact	Plant radish and carrot seeds in the same row. Quick-germinating radish seeds help mark the row where slow-germinating carrot seeds eventually sprout. Radishes will be ready to harvest before carrots need the space.

Snapshot	One of the quickest, easiest garden vegetables to grow, radishes are usually among the first to harvest in the spring. They require little space and can be easily tucked into vacant soil in containers, raised beds, and in-ground gardens.
Starting	Radishes don’t require any special soil. Scatter seeds or sow them in rows, but don’t spread them too thickly, because they usually germinate quite well. For multiple harvests, schedule succession plantings 10 days apart up until about a month before hot weather sets in.
Growing	Radishes usually grow well on their own without much intervention. Thin extra sprouts to 1 to 2 inches apart and mulch to prevent weeds. Watch for the radish roots to begin poking out of the soil, signaling they’re ready to harvest.
Harvesting and Storing	Begin harvesting when the tops of the radishes start to emerge from the soil, usually when they’re about 1 inch in diameter. Don’t leave them in the ground too long; the longer they stay in the soil, the tougher they’ll get. You can leave a few in the ground to bolt and flower. Beneficial insects love these flowers, and left to go to seed, radishes can self-sow for another crop.
Common Problem	When radishes are grown in the heat of the summer (or when you delay harvest for too long), the taste becomes sharp, pungent, and sometimes bitter or spicy. For a sweeter flavor, harvest before hot weather sets in.