Watermelon radishes are a fun and tasty addition to any vegetable garden. Sometimes mistaken for turnips, these radishes are a large, round variety of daikon radish. Their name comes from their pale green rinds and brilliant magenta centers.
Watermelon radishes have a sweet, mild flavor compared to traditional radishes. They become sweeter as they mature, so you can delay harvesting them until the flavor is perfect.
These radishes thrive when planted in early spring and take 55–60 days to mature. They are easy to grow from seeds planted directly in your garden. Watermelon radishes can grow quite large, some up to 5 lb.
Growing Conditions
Watermelon radishes prefer full sun, but they are still cool-season vegetables. They can tolerate partial shade but may not grow as large.
Like other radishes, watermelon radishes grow best in loose, well-drained soil rich in organic matter. Adding compost to your garden bed will create ideal conditions.
Water regularly to keep the soil moist, especially when the radishes are young. Mature radishes are more drought-tolerant.
When to Plant
Plant watermelon radish seeds 4–6 weeks before the last expected spring frost. They can handle light frosts but not hard freezes.
You can succession plant small batches every 2–3 weeks for a continuous harvest. You can also sow seeds in late summer or early fall in warm climates.
How to Plant
Sow seeds 1/2 inch deep and 2 in apart in rows spaced 12–18 in apart. Thin the seedlings to 4–6 in apart when they are 2–3 in tall.
Before planting, mix a balanced organic fertilizer into the soil according to package directions. Side-dress growing plants with more fertilizer four weeks after sprouting.
Growing Tips
- Use row covers at planting to prevent insect pests like cabbage maggots, flea beetles, and root maggots from attacking young plants. Remove row covers when plants start to flower.
- Handpick slugs, aphids, and other pests when you spot them to prevent damage.
- Watermelon radishes tend to push up out of the soil as they grow. Hill soil up around the shoulders of the radish to avoid greening.
- Rotate where you plant watermelon radishes each year to prevent disease. Avoid planting them in the same spot for 3–4 years.
Harvesting
Begin harvesting radishes when the diameter reaches at least 2 in and before they grow to 4.
Use a garden fork to loosen the soil and pull radishes gently from the ground. Do not pull too firmly, or you may break the skin. Clip off the long taproots and leaf tops, leaving 1–2 in of stem attached.
Storing the Harvest
Watermelon radishes can last in your refrigerator for 2–4 weeks. Wrap them in a paper towel or put them in a plastic bag before placing them in the crisper drawer. Storing them this way will prevent moisture buildup.
Therefore, wash radishes just before eating, not before storing them, or they will spoil faster. You can also pickle sliced radishes to preserve them.
Using Watermelon Radishes
Watermelon radishes are versatile vegetables you can use in many dishes, both raw in salads or cooked in soups and roasts. Their mild, sweet flavor pairs well with other ingredients.
Thinly slice radishes and add them to salads for a pop of color and crunch. You can also eat them solo with a sprinkle of salt.
Roast chunks of watermelon radish as a flavorful side dish. Or add diced radishes to soups and stews.
Substitute watermelon radish anywhere you would use turnips or rutabagas. They make an excellent addition to pot roasts and braised meat dishes.
So, Is Planting Watermelon Radishes Worth It?
Watermelon radishes are one of the most unique vegetables you can grow. Aside from being a conversation starter, their sweet, mild taste is a nice change from hot traditional radishes. Kids and adults alike will enjoy biting into the colorful interior.
The seeds are easy to start in spring, and the radishes require minimal care. Just be sure to harvest them on time before they crack open. If you have the space to devote to these giants, watermelon radishes are worth planting for their novelty factor alone.
FAQs About Watermelon Radishes
What do watermelon radishes taste like?
Watermelon radishes have a very mild, sweet flavor compared to most radishes. They tend to become sweeter and less pungent as they mature.
How big do watermelon radishes grow?
On average, watermelon radishes reach up to 4 in (diameter) and can weigh as much as 2 lb each.
What color are watermelon radishes on the inside?
When you slice open a watermelon radish, the interior is a brilliant magenta that resembles the inside of a watermelon. The contrast with the pale green skin is visually striking.
Can you eat the greens of watermelon radishes?
Yes, the leafy green tops are edible. They have a strong, spicy flavor similar to turnip greens. The greens are good sautéed or added fresh to salads.
Are watermelon radishes easy to grow?
Watermelon radishes are one of the easiest vegetables to grow. The seeds germinate readily and are hardy plants. They have minimal pest or disease problems.
