How big do Radishes get? (Can we grow bigger Radishes?)

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How big do Radishes get? You might be wondering how big radishes will get if you intend to cultivate them in your yard this year. By doing so, you may calculate how many plants and how much room you’ll need for your radish crop.

Key takeaways:

  • The root diameter of radish plants ranges from 1 to 4 inches (2.5 to 10.2 centimeters), while their height and width are 4 to 14 inches (10.2 to 35.6 centimeters) and 3 to 14 inches (7.6 to 35.6 centimeters), respectively.
  • Some tall radish types, like Daikon, can develop roots that are between eight and fourteen inches long (20.3 to 35.6 centimeters).

Of course, how well you take care of your plants will affect the quality of your radishes.

Let’s examine radishes in more detail, including their size, growing circumstances, and maturation period.

How big do Radishes get?

The stalks and leaves of radish plants can reach heights of 4 to 14 inches (10.2 to 35.6 centimeters) above ground and 3 to 14 inches (7.6 to 35.6 centimeters). One to two inches (2.5 to 5.1 cm) may be the maximum diameter of the roots of many small, spherical radish types.

The diameter of certain larger round radishes can reach 3 or 4 inches (7.6 to 10.2 cm). But before they become too big, you should pick your radishes. If you don’t, you’ll get radishes with a bitter taste. The longest and thinnest radish cultivars, like daikon, can reach heights of 8 to 14 inches (20.3 to 35.6 centimeters).

For more such plant related-articles, you may also read, Top 7 Carrot Varieties for Containers (and Where to get Seeds?)

How to Grow Bigger Radishes?

Time of Plantation

As soon as you can work the soil, you can plant radishes. They cannot stand high temperatures and will flee in the heat of the late summer. Therefore, sow a lot of them in the early spring. Later in the summer, you can start planting them once more in preparation for the fall.

Sunlight Requirements

To completely develop, radishes require around 6 hours of direct sunlight each day. Although they can take some shade, you’ll get the greatest results if no other veggies completely block their light. Because of this, radishes make a great container crop.

Fertilizer Use

Don’t overly enrich the soil when growing them, whether in the ground or a container. Much nitrogen is not suitable for radishes. You’ll get the most gorgeous radish tops with a frail tiny pink root if the soil is overly nitrogenous. 

We can all agree that the goal is to cultivate the root, not the top, even though radish leaves are edible (and rather nice). Therefore, you don’t need to fertilize the soil before planting your seedlings this time. Radishes can therefore be grown in soil that is a little low in nutrients and still thrives.

Loosen the Soil

Since radishes are a root crop, you want to make it as simple as possible for the portion that grows underground to develop and grow. The soil must be well worked for it to be loose and not compacted. The root will be more compressed by heavy soil, preventing radish growth. 

The soil should be loose to a depth of 4–6 inches, whether in a container or on the ground. When watering, use a light setting on your garden hose, such as a gentle spray. It also works excellently using a watering can with a sprinkler head. 

Better yet, once the plant has germinated, use a tiny cup and bucket to water directly at the base of the plant to save water and keep the soil moist and loose. To grow plants in containers like beets are grown in containers, I like to use a 3:1 mixture of potting soil and peat moss. The peat moss aids in keeping the soil moist.


Radishes can usually tell when they are being crowded out. Simply put, the radishes won’t grow well if they are planted too closely together. And while the majority of information instructs to sow and then thin to 2″ apart, I’ve found that planting a single seed every 3″ has given me the best results. 

This conserves seeds and provides ample space for the radishes. Consider creating your seed tape using your preferred radish kinds to make sowing radishes simpler. It is inexpensive, rapid, and minimizes seed waste. 

Radishes are fairly good at germinating, so you’ll often get sprouts from every seed you sow. It happens that one or two seeds won’t sprout, but you can always plant another seed in that spot. Your seeds should be sown between 14″ and 12″ deep in terms of depth. 

Once more, if the seed is buried too deeply, the radish won’t be able to grow as it should due to the weight of the earth. The majority of the growth should take place in the top few inches of soil, if possible. After you’ve planted your seeds, carefully cover them with soil by running your palm over the top. Give the seeds a thorough yet gentle soak before watering them in.

Maintain Soil Moistness

Maintaining constant moisture in the soil is crucial, especially during germination. While you wait for the radishes to emerge, you’ll probably need to water them every day. You can water less regularly when the leaves have fallen. 

You don’t want them to fully dry out, though. When the soil is just barely moist, radishes grow best. Don’t rely on your eyes; place your finger in the soil and water the plants once the top 1 to 2 inches of soil are dry. 


You now have a much better understanding of how large radishes can grow, both in terms of the underground root and the stalks above ground. Additionally, you are more knowledgeable about the care required to guarantee a robust crop of radishes in the garden this year.

Thanks for reading! Happy gardening! 

Becky Decker