Radishes: Planting, Growing, and Harvesting Radishes | The Old Farmer's Almanac



radishes at a roadside market

Photo Credit
Annette McCarthy
Botanical Name
Raphanus sativus
Plant Type
Sun Exposure
Soil pH

Planting, Growing, and Harvesting Radishes

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Radishes are planted in the cool temperatures of spring and autumn, and this hardy root vegetable is ready to harvest in mere weeks. Learn how easy it is to grow radishes.

About Radishes

Radishes are an annual root vegetable and a member of the Brassicaceae or cabbage family, which includes broccoli, cabbage, cauliflower, kale, collards, and, as the name suggests, horseradish. The entire plant is edible—from root to leaves—and can be enjoyed raw or cooked. (See Cooking notes below.)

Seeds can be planted in both the spring and the fall, but sowing should be suspended when warm temperatures arrive (70 degrees or higher); this causes radishes to bolt, making them essentially useless. Otherwise, radishes are one of the easiest vegetables to grow. 

Because radishes mature so quickly, you can sow them anywhere there is an empty space or sow in between rows of other vegetables such as carrots or beets. Radishes also happen to make excellent companion plants to help deter pests from other vegetables.



Choose a sunny spot that gets at least six hours of sun a day. If radishes are planted in too much shade, or even where neighboring vegetable plants shade them, they will put all their energy into producing larger leaves. 

Till the soil (roots do not grow well in compacted soil) and remove any rocks. If the soil is clay, mix in some organic matter to loosen and improve drainage. If you’re planting longer varieties (such as ‘White Icicle”), till to a depth of 8 inches.

When to Plant Radishes

  • For a spring planting, sow seeds 4 to 6 weeks before the last spring frost.
  • For a fall crop, sow seeds 4 to 6 weeks before the first fall frost.

 See local frost datecs here.

How to Plant Radishes

  • Add organic matter before sowing but also avoid fresh manure or fertilizers high in nitrogen; overly rich soil will encourage lush foliage at the expense of radish roots.
  • Radish seeds have a fairly long shelf life. Don’t be afraid to plant radish seeds that are up to 5 years old. All may not germinate, but you’ll have plenty that will.
  • Direct-sow seeds outdoors about 1/2-inch deep and cover loosely with soil. Space 1 inch apart in rows 12 inches apart. Water seeds thoroughly, down to 6 inches deep.
  • Sow another round of seeds every 10 days or so while weather is still cool for a continuous harvest of radishes in the late spring and early summer.

Check out this video to learn how to plant radishes:


Thinning Radishes

Thinning” is probably the most important step in growing radishes. Once the seedlings are 2 inches tall or about a week old, it’s important to thin radishes to three-inch spacings. Crowded radishes do not grow well, and you’ll end up getting small, shriveled, inedible roots.

To thin, just snip the greens at the soil line. The thinnings are edible, so add them to a salad! Or, if thinnings have been carefully extracted with roots, leaves, and stem intact, replant them. Transplants might be a bit stressed, but they should recover.

Photo credit: Larisa Lofitskaya/Shutterstock

Watering Radishes

  • Consistent, even moisture is key. Don’t let it dry out, or you’ll get pithy, pungent roots but don’t let it get waterlogged, or the roots will rot. A drip irrigation system is a great way to achieve this. 
  • Mulch the radishes with compost enriched with wood ashes to help retain moisture in dry conditions as well as keep root maggots at bay.
  • Weed often; weeds will quickly crowd out radishes.

The biggest mistake gardeners make with spring radishes is leaving them in the ground past their maturity, then they will get tough and taste starchy. Winter radishes, on the other hand, can keep in the ground for a few weeks after they mature, if the weather is cool. Finish the harvest before frost. 

  • To harvest, check your seed packet! Different types of radishes have different grow times. Some varieties are pulled as soon as 3 weeks after planting, when roots are approximately 1 inch in diameter. Pull one out as a test. 
  • Another good sign that your radish root is doing well is that the green growth above the soil is 6 to 8 inches tall. 
  • Finally, you should see or feel the “shoulder” or top part of the radish pushing up against the topsoil.

If some radishes bolt before you have a chance to harvest them, leave a few to develop seedpods. The seedpods, which look like tiny bean or pea pods, are actually quite tasty in a salad.

How to Store Radishes

  • Cut off the tops and the thin root tail, wash the radishes, and dry them thoroughly. Store in produce or zip-top bags in the crisper drawer of the refrigerator.
  • Radish greens can be stored separately for up to 3 days. Put them in a separate produce bag with a dry paper towel.


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Wit and Wisdom
  • For hoarseness, swallow slowly the juice of radishes. –18th-century remedy.
  • Got a mosquito bite? Apply radish juice to take away the sting and itching.
Radish Pests and Diseases
Cabbage root maggotsInsectsWilted/stunted plants; off-color leaves; larvae feeding on rootsUse collars around seedling stems; monitor adults with yellow sticky traps; use row covers; destroy crop residue; till soil in fall; rotate crops
Cabbage wormsInsectsLeaves have large, ragged holes or are skeletonized; heads bored; dark green excrement; yellowish eggs laid singly on leaf undersidesHandpick; use row covers; add native plants to invite beneficial insects; grow companion plants (especially thyme); spray Bacillus thuringiensis (a bacteria that affects larvae and grubs)
ClubrootFungusWilted/stunted plants; yellow leaves; roots appear swollen/distortedDestroy infected plants; solarize soil; maintain soil pH of around 7.2; disinfect tools; rotate crops
Flea beetlesInsectNumerous tiny holes in leavesUse row covers; mulch heavily; add native plants to invite beneficial insects
White rustFungusChalk-white blisters mainly on leaf undersides; small, yellow-green spots or blisters, sometimes in circular arrangement, on upper leaf surfaces; possible distortion or galls; stems may also be infectedDestroy infected plants; choose resistant varieties; weed; destroy crop residue; rotate crops
Cooking Notes

Many folks do not realize that radishes have uses well beyond the salad garnish! Radishes are great for pickling with carrots or to be fermented into kimchi. The small types can be snacked on whole (with their green tops as handles), or dipped into salted butter and lime. Of course, radishes can also be grated into cabbage slaws to add some flavor.

Radishes can also be cooked. You can roast halved radishes until buttery and tender. And the green tops can be sauteéd in olive oil with some garlic or even made into pesto.