Want to grow radishes but you’re not sure where to start? Tried before and failed? Join us to learn all of the tips and tricks to successfully grow radishes from start to finish, even if you think you have a black thumb! In this post, we will help you choose the best variety, learn all the secrets to planting, growing, and harvesting.

Welcome to the “How to Grow” Series

When we first started teaching Black Thumb Garden Club classes, we created these booklets that we called Veggie Fact Sheets or Fruit Fact Sheets or Herb Fact Sheets…see where we were going with that?

Each fact sheet highlighted commonly grown veggies, fruits, and herbs. We encouraged our class members to look through these booklets as they were deciding what to plant in their gardens. We kept the information to one page (which was hard for some veggies) and kept it very simple.

These Fact Sheets didn’t make the cut when we wrote the Black Thumb Garden Club Workbook, but we saw the need to still have detailed information available to help beginning gardeners make decisions about what to plant.

So we bring you the first installment in our weekly How To Grow Series.

First up, the mighty Radish! 

Radishes are a great starter vegetable. They are easy to grow and have a quick turnaround time… we are talking a month or less.

They also take of very little space. Many gardeners don’t dedicate a particular spot to radishes, but choose instead to plant them in between slower growing plants.

Because they are so quick to grow, I choose to dedicate one square of my square foot garden to radishes and just replant as soon as they are done growing. 

Radishes prefer cooler weather and most will not grow once the weather begins to warm up.

Choosing the Best Radish Variety for Your Garden

Some radishes are meant to be grown in the spring, while others are more suited to the winter as they grow just a bit slower. Winter varieties include “China Rose’ and ‘Long Black Spanish’.

A quick glance at any seed catalog will show you that there are lots of different radish varieties.

In addition to the traditional red fleshed, white interior varieties commonly purchased at the grocery store (known as ‘Cherry Belle’), there are all white varieties and others that are both red and white fleshed.

This year, I am growing a variety called ‘French Breakfast’. They’re oblong instead of round and so yummy! There are several other oblong varieties as well. 

How to Grow (aka How Not to Kill) Radishes

Radishes deter cucumber beetles and make lettuce tender - making them great companion plants to cucumbers and lettuce as well as beets, spinach, peas, and melons.

You can plant radishes about 4-6 weeks before the average last frost date… plant as soon as the soil is workable.

Always read the seed packet before planting, but most require a planting depth of 1/2”. They only need to be planted a few inches apart if going in a traditional garden. In a square foot garden, you can plant 16 per square foot.

While growing, make sure they constantly have even moisture.

You can continue to plant radishes in succession every two weeks until the temperature reaches a steady 65 degrees or warmer. After that, it will be too warm for radishes to grow well, although oblong varieties fare a bit better in warmer weather.

How (and When) to Harvest Radishes

Because radishes grow so quickly, you need to watch them closely and harvest as soon as they are ready. For round varieties, pull them up when they are about 1 inch in diameter. Oblong varieties will need to be about 2 inches long.

Waiting too long will lead to a bitter radish. Their leaves are edible and rumor has it that if you let one or two go to seed, their seeds are quite tasty on salad.

Radish Fast Facts

Crop Rotation Group: Root Vegetable

Planting Method: Direct Sow

Needed Structural Support: None

Days to Harvest: 20-30

Number per square foot: 16

We will be focusing on a new plant each week. Which fruit, veggie, or herb do you want us to focus on next? Leave your suggestions in the comments! 

Don’t forget to join us in the Facebook group and grab your copy of the Black Thumb Garden Club Workbook!

See you there,

Mariah