There is nothing quite like a fresh home-grown radish with that fresh crisp snap, spicy bite, or vibrant colors. Nor the pleasant welcome they bring to spring garden as one of the first vegetables ready to harvest. But sometimes, radishes can be finicky to grow in the garden. Farmer Nathan is here with some easy tips to grow great radishes to help you on your road to success!
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When to plant
I like to plant when there is not a chance of frost. This is important in the spring when the young seedlings could be damaged by a late frost. The frost might not kill them, but it could greatly slow down their growth to maturity. (If you want to try and get extra early radishes, check out our other post on Protect your garden from frost – 4 simple ways to cover.) Alternatively, fall plantings of radishes, that are 6 weeks or older will survive through a cold snap. This age ensures that the plant is large enough to sustain itself through frost and continue to grow.
Old farmers often swear by planting by the moon, which means they would plant root crops as the moon wanes. (You can learn more about growing vegetables by the moon here.) I can’t say there is scientific data to back this up, but there may be merit to what they are suggesting. When I have planted our root crops just after a full moon, the resulting crop has been stronger and healthier. This generally leads to an increased yield close to the new moon. If you are like me though, the schedule doesn’t always allow to plant at this specific time. Even so, the rest of the tips can provide additional success.
Garden preparation
When the moon phase doesn’t line up, I like to spend more time on the garden preparation. In the spring, my favorite tip to grow great radishes is to loosen the soil. In order to grow properly, most radishes like loose soil. I use a tool called the claw for this purpose as it is easy on the land and the body. You do not need to feel like you have to dig to China to loosen the soil. Six inches of depth is more than enough for most radishes varieties. If you have some compost, I love to add an inch or so before planting to help keep the weeds down while giving the radishes a nutritional boost.
If you have heavy clay where you live, incorporating peat moss and manure can help balance the pH of the soil while keeping it loose. For sandy soil, you may find maintaining moisture to be an issue. In this case, I like to use a light mulch after the radishes germinate to trap a bit more moisture. And if you are lucky to have soft loamy soil, you should be nicely situated to grow beautiful radishes without as many amendments.
How close to plant & weed care
Radishes can be planted relatively close together. I like my salad radishes about 1 inch apart in rows 3 inches apart. If you like daikon varieties, these like a little more elbow room and I usually plant 3 inches apart in rows 6 inches apart. What is great about radishes is with how close they are planted, weeds are not nearly as much of an issue. As soon as the true leaves emerge is the cue to hit the garden bed with a wire weeder or hand weed. At this stage, the radishes seedlings are strong enough to handle weeds being pulled around them. It won’t be long and you will find the radish leaves touching. When this happens, weeds are no longer a concern as light can no longer penetrate the leaf canopy for the weeds to grow.
How to water
Another tips to grow great radishes is managing water. Radishes do not like their feet too wet. Once the plants are established, I like to reduce watering so that the soil almost dries out between waterings. This is about 1.5 inches of water per week. Too little water and the radishes won’t form right. And too much water and the radishes will crack or form in knotted twists. I like to plant my radishes in a dryer part of the garden where it doesn’t hold as much water. If your whole garden is heavy clay or tends to hold water, try adding more compost and/or sand. This should help loosen the soil enabling the radish roots to grow better.
Fertilizing
Radishes do not like too much nitrogen. I have made the mistake many times to have a good and rich bed with lots of compost just to receive at harvest time beautiful radishes greens without any roots. My secret weapon to help against poor root growth is feeding the soil and via the leaves of the plants. Water soluble kelp works wonders at helping bulk up radish roots. Simply spray once per week while they grow, and it should help with the development of beautiful radishes. For feeding the soil, I like to sprinkle Thorovin Kelp lightly across the growing area. This feeds the soil microbes, which can help with the accessibility of absorption of phosphorus. And phosphorus is one of the key ingredients to great radishes.
How to know when to harvest?
One of the tips to grow great radishes is knowing when to harvest them. This can be tricky as at times, the whole radish can be completely underground. If there is any uncertainty, I like to take my finger and lightly dig around the radish plant to gauge the size of the radish. For a salad radish, I shoot for around a ping pong ball for the average size. As soon as the radish has reached this size, simply pull lightly on the tops of the radish and the radish will pop out!
I hope these tips help you achieve great success in your journey to grow delicious radishes.
