Special Gift Offer
URL:
http://www.gardengatemagazine.com/newsletter/2022/09/15/how-to-grow-radishes/
Share:

How to Grow Radishes

By: Marisa Reyes
Fall is a great time to plant radishes. Find out where to order seeds and how to plant this cool-season vegetable in both spring and fall!

Radishes growing in the ground: Radishes are easy to sow directly into soil in spring or fall.

Did you know you can grow radishes in spring or fall?

I used to think that radishes were the perfect early spring vegetable. Then I learned that you can also grow them in fall and have been growing them for several months a year ever since. Because they’re so fast growing (seedlings typically emerge 3 to 7 days after you plant), they’re great candidates for succession planting, and you can get several harvests in a single growing season. Plant them between other crops, in containers, or anywhere you can find an empty space. Radishes are typically grown for their spicy and peppery taproot.

There’s so much variety: Radishes come in all kinds of shapes, from the traditional globes to medium oblong shapes and longer daikon types. And you can find every color in the rainbow but blue, even black and white. Little-known fact: The entire radish plant is edible!

  • Radish seedlings, or microgreens, add a kick to salads and sandwiches.
  • The mature foliage can be used in sauces, soups, salads or served on its own.
  • And even the seed pods can be eaten straight off of the plant, tossed in salads or pickled!

You Might Also Like:
Radish Sprouting and Microgreen Seeds
Microgreen Growing Kit Self Watering

Fall and spring radish varieties

Although you can plant the same seeds you traditionally grow in spring for a quick fall crop, there is also an entire group considered “fall radishes.” Because temperatures get too warm before they mature, they aren’t good candidates for spring sowing, but they are very cold tolerant, and you can harvest these little nuggets until the ground freezes every year. Scroll down to learn about the key differences between the two types and meet some varieties I think you should try in the gallery at the bottom of the article. Read on to learn how to grow them in both spring and fall!

Where to buy radish seeds


Harvested radishes: Radishes look their best when harvested at the right time like this perfect red globe variety

How to grow the best radishes

Radishes will germinate in temperatures as low as 40 degrees F. For a fall crop of radishes, sow seeds 4 to 6 weeks before your average first fall frost. For a spring crop, sow them 4 to 6 weeks before the average last frost date. Check here to find your average frost dates.

How to plant radishes

The planting method is the same for all radish types:

  • Direct sow seeds outdoors about ½ inch deep, spacing them 1 inch apart in rows 12 inches apart and cover loosely with soil.
  • Soak the soil when you plant, then make sure seedlings and growing plants get about 1 inch of water per week after that.
  • Sow seeds every 10 days or so for a continuous harvest. Read the seed packet and stop when your plants won’t have enough time to mature.

Don't forget to mulch!

All radishes are tolerant of frost. In fact, fall varieties can survive temps as low as 20 degrees F. However, to keep the soil from freezing (so you can continue to harvest), throw down a 4-inch layer of straw for mulch as soon as you’re expecting temperatures below 28 degrees F.

Straw mulch is also a good idea in spring. It’ll help keep the soil between 60 and 70 degrees F to prevent bolting, or early flowering, which negatively impacts radish shape and flavor.

You Might Also Like:
Are You Using the Right Type of Mulch?
Cool Season Vegetables to Plant in Fall
Five Easy Vegetables to Grow

Thinning radish seedlings before and after: Be sure to remove overcrowded seedlings. Snip 2-inch-tall seedlings at the soil line about 3 inches apart. Crowded radishes do not grow well, and you’ll end up getting small, shriveled, inedible roots.

Thinning radish seedlings

“Thinning” is undoubtedly the most important step of growing radishes. Once the seedlings are 2 inches tall or about a week old, thin them to about 3 inches apart. To thin, snip the greens at the soil line. The photos above show how sparse your thinned row may look at first, but you need to do it to give those roots a chance to fill out. Don’t waste those tops, though: Wash the microgreens up and put them in a salad!


Harvesting radishes

It can be tricky to tell if your radishes are ready to harvest: If pulled to early, they could be too small for eating; and if left too long, they become woody and tough.

I use two methods when deciding if my radishes are ready to harvest. First, I scrape away the soil from the top of the root using my fingers or a small trowel. Roots of mature radishes are roughly 1 inch in length, depending on the variety (again, refer to seed packet). If the roots are still too small, I recover them with soil and let them continue to grow.

But sometimes I just use the “go for it” method: I pull a couple out and spot check. If the root is large enough to eat and still firm to the touch, it is time to harvest. Spring radishes mature quickly, so I check mine every few days. You won’t need to do this as often for fall types since they store well in the ground past maturity, but you should pull them before the ground freezes.

What's wrong with my radishes?

Unfortunately, not every radish comes out of the ground as perfect as these. Here are a few problems you might encounter and what causes them.

  • Super spicy roots= high soil temperature, left in the ground too long
  • Woody and pithy roots= high soil temperature, inconsistent watering
  • Cracked roots= left in the ground for too long, inconsistent watering
  • All greens and no root= high air temperatures, crowded planting, not enough sun

You Might Also Like:
Companion Plantings for Vegetable Gardens
Growing Vegetables Indoors
How to Build a Keyhole Garden Bed


Storing radishes

Once the radishes leave the ground, cut off the greens, wash the roots and store them in the refrigerator. Storage time depends on the variety of radish you decided to grow. When you cut the tops from your radishes, don’t toss them. Instead, add them to salads, soups, sauces or sautés. They’ll store well for a few days in the refrigerator: Just wash, pat them dry and place them in a resealable plastic bag.

Dragons Tail rat tailed radish 2: Rat-tailed radishes are grown specifically for their tasty pods. They don’t form edible roots.

Radish seed pods

Radish seed pods are not only edible, but you might be surprised at how delicious they are! You’ll need to let the plant bolt, or flower, for seed pods to form. They are slightly spicy but milder than the root. Harvest radish seed pods when they are young and bright green, or they turn bitter and woody. Just rinse and pat them dry before storing for up to a week in the refrigerator. Eat them raw, in salads or sauteed in a stir fry. I personally love to pickle them!


Fall vs. Spring radishes

There are a few differences between spring and fall radishes, we've compared the two below:

Spring Radishes

  • Mature in 35 days or less
  • Become bitter when overripe, left in ground for too long or temperatures rise
  • Store well for only a week or so
  • Greens are soft and small, have a mild bite and slightly fuzzy texture
  • Start to bolt when temperatures are consistently above 70 degrees F

Fall radishes

  • Can take 30 to 80 days to mature
  • Consistent fresh, crisp taste, whether harvested early or late
  • Store well for months
  • Abundant greens are tender and mild and can be picked before the root matures without affecting growth
  • Start to die off when temperatures consistently stay below 20 degrees F

Radish Seeds We Recommend:
'Watermelon' radish seeds
Garden Party Radish seed mix
Crimson Crunch radish

Radish varieties to grow

There are a wide range of radishes you can grow in spring and fall. Check out the gallery below that includes both spring and fall radishes, each type is noted for when it is best grown.

‘French Breakfast’ radish

‘French Breakfast’ radish

Best grown in spring; small to medium-sized oblong bicolor heirloom; mild peppery raw flavor turns slightly sweet and nutty when cooked; 23 days to maturity

‘Golden Helios’ radish

‘Golden Helios’ radish

Best grown in spring; small round or oblong golden heirloom; mild sweet peppery flavor; 32 days to maturity

‘Watermelon’ radish

‘Watermelon’ radish

Best grown in fall; medium to large globe- shaped radish, white on the outside, red inside; mild sweet flavor; 60 days to maturity

‘Black Spanish’ radish

‘Black Spanish’ radish

Best grown in fall; large globe-shaped roots; crisp, pungent and spicy; 70 days to maturity

‘Royal Purple’ radish

‘Royal Purple’ radish

Best grown in spring; medium-sized round variety; disease and pest resistant; mild, sweet taste and crunchy texture; 33 days to maturity

‘Sparkler’ radish

‘Sparkler’ radish

Best grown in spring; medium-sized round to oval shaped bicolor heirloom; crisp tender and sweet; 25 days to maturity

‘White Icicle’ radish

‘White Icicle’ radish

Best grown in fall; medium-sized long daikon heirloom; mild flavor with crisp texture; 30 days to maturity

‘Salad Rose’ radish

‘Salad Rose’ radish

Best grown in fall; large long daikon variety; peppery taste with sweet undertones; 35 days to maturity

‘French Breakfast’ radish

‘French Breakfast’ radish

Best grown in spring; small to medium-sized oblong bicolor heirloom; mild peppery raw flavor turns slightly sweet and nutty when cooked; 23 days to maturity

‘Royal Purple’ radish

‘Royal Purple’ radish

Best grown in spring; medium-sized round variety; disease and pest resistant; mild, sweet taste and crunchy texture; 33 days to maturity

‘Golden Helios’ radish

‘Golden Helios’ radish

Best grown in spring; small round or oblong golden heirloom; mild sweet peppery flavor; 32 days to maturity

‘Sparkler’ radish

‘Sparkler’ radish

Best grown in spring; medium-sized round to oval shaped bicolor heirloom; crisp tender and sweet; 25 days to maturity

‘Watermelon’ radish

‘Watermelon’ radish

Best grown in fall; medium to large globe- shaped radish, white on the outside, red inside; mild sweet flavor; 60 days to maturity

‘White Icicle’ radish

‘White Icicle’ radish

Best grown in fall; medium-sized long daikon heirloom; mild flavor with crisp texture; 30 days to maturity

‘Black Spanish’ radish

‘Black Spanish’ radish

Best grown in fall; large globe-shaped roots; crisp, pungent and spicy; 70 days to maturity

‘Salad Rose’ radish

‘Salad Rose’ radish

Best grown in fall; large long daikon variety; peppery taste with sweet undertones; 35 days to maturity

Published: Sept. 13, 2022
Share:
GDT Notes Ad_BILU22_zone5

Product Recommendations

Here are some supplies and tools we find essential in our everyday work in the garden. We may receive a commission from sales referred by our links; however, we have carefully selected these products for their usefulness and quality.

GDT Notes Ad_BILU22_zone6

Related Tags

fall seeds spring vegetables

Also in This Newsletter


GG_free-issue_Zone7&10_v01_mobile-version
Last Week’s Newsletter

September 8, 2022

3 Simple Ways to Divide Plants

Whether you’re looking for more of your favorite plant or just hoping to revive an overcrowded one, you’ll benefit from these easy tips for dividing plants.

Fall Garden Checklist

Taking care of your fall garden makes your garden healthy and gorgeous next year, too. Here’s a fall garden checklist that will help you know what to do now.

How to Grow Garlic

Have you ever grown garlic? It's so easy and fall is a great time to plant! Find out where to buy bulbs and how to grow your own with tips from Niki Jabbour here.

GDT Free Issue zone15 Spring