How to grow radishes

Radishes come in a range of different colours
Image: Radish 'Rainbow Mixed' from Thompson & Morgan

In the race for a quick crop, radishes are the undisputed winners! Maturing in as little as 30 days from sowing, they make superb 'gap fillers' when space becomes available. These crunchy, little vegetables are undemanding and easy to grow - happily thriving in the ground, containers and window boxes. Whether you want to enjoy traditional favourites or new and interesting varieties that can't be bought in a supermarket, here's how to grow your own radishes from seed. 

Browse our full range of radish seeds for inspiration. 

Best radish varieties to grow at home 

Spicy-flavoured 'Diana' matures in 25 days from sowing
Image: Radish 'Diana' from Thompson & Morgan

• Colour: For crunchy, colourful salads, choose Thompson & Morgan's Radish 'Rainbow Mixed' in red, white and gold. If you prefer your radish in stir fries, then the oriental Daikon Radish 'Misato Rose Flesh; is ideal for adding a splash of colour.
• Heritage: If you like traditional varieties then the mild and crisp Radish 'Poloneza' has stood the test of time. This attractive variety is useful for extending the season as it grows well under cloches or in the greenhouse, and resists bolting particularly well.
• Flavour: Whether you like them mild or peppery, there's a radish to suit every palate. For a powerful bite, try Radish 'Vienna', or the ever-popular Radish 'French Breakfast' whose long pink and white roots certainly pack a punch. If you prefer a mild, refreshing flavour then 'Cherry Belle' may suit your taste buds better.
• Winter: Don't leave your veg patch standing empty over winter. Mooli Radish 'Neptune' brings an exotic twist to your mealtimes and can be fried, shredded, baked or boiled. These Asian relatives of our summer radishes are harvested in late autumn when most crops have finished. 

How to sow radish seeds

These sweet, mild radishes have bright red skins and a crisp, crunchy texture
Image: Radish 'Cherry Belle' from Thompson & Morgan

Because they're such quick growers, it's best to stagger your sowings and only sow a small pinch of seed at a time. As each pinch of seed begins to germinate, sow another pinch. In this way you'll have a constant supply throughout the summer. 

• Direct sow radish seeds outdoors from April to August in soil which has been prepared to a fine tilth. 
• You can lengthen the growing season by sowing under glass or cloches during March and September, provided that the temperature remains around 15-20C (59-68F). 
• After sowing, cover the seeds lightly with just 1cm of soil. In just a matter of days, the seeds will germinate. 
• If you have sown them thinly enough, they shouldn't need much thinning out. Try to aim for one plant every 2.5cm (1") interval. 
• Prevent your radishes from running to seed by keeping them cool and well-watered, particularly during hot, dry periods. Excessive watering should also be avoided as this will encourage radish leaf growth instead of root development. 
• Harvest your radishes 3 to 4 weeks after sowing when the roots reach a reasonable size. Simply pull the roots up as and when you need them. Don't leave them too long - they're best enjoyed young and crunchy!

Where to sow radish seeds

Radishes growing in raised beds
Image: Thompson & Morgan

Radishes are perfect for inter-planting between the other crops that take much longer to mature. Sow them between rows of tomatoes, potatoes, peas and sweet peppers to maximise the potential of your plot. They can be harvested long before their companion crops are ready, without causing them any disturbance.

Radishes prefer cool, moist soil. They tend to bolt and become woody in hot conditions, so a cooler, part-shaded spot under leafier crops provides much-needed shelter as the summer temperatures begin to rise.

You can also sow radish seeds in containers, window boxes, raised beds or even amongst your flower beds for clever cottage-style productivity. 

Radish pests and diseases

A healthy crop of colourful radishes
Image: Thompson & Morgan

Radishes grow quickly and usually have very few problems. Here are some that you might encounter along with some tips to prevent them. 

• Flea beetle: Flea Beetle can be a problem by nibbling holes in the foliage. Growing seedlings under horticultural fleece can help to prevent Flea Beetle.
• Slugs and snails: These common pests can attack seedlings, especially in damp conditions. Check your plants regularly, remove any offenders by hand and encourage plenty of natural predators like birds, frogs, and hedgehogs. 

Quick-growing radish seeds are just one of the tasty options available in our salad seed range! For more information about growing your own salad crops, head to our comprehensive salad advice hub.