- Author: Erin Mahaney
Each year, I try to grow at least one new plant in my vegetable garden. Whether the trial vegetable is a success is based on two factors: (1) whether the plant actually grows; and (2) whether anyone in my family will besides me will voluntarily eat it. So far, my overall success rate is pretty low, in large part because my success rate for factor #2 is zero. But I’ve decided that’s OK—it’s still fun to try new things!
Last year, I tried growing watermelon radish for the first time. Watermelon radish (Raphanus sativus 'Watermelon') is a larger radish that is white with pale green shoulders on the outside and red on the inside, looking a bit—not surprisingly—like a watermelon! It grows to approximately 3” (the size of a tennis ball) and even larger if you let it.
The watermelon radish is a winter variety of radish that is best grown in cool weather. The seeds should be planted in late summer or early fall, although last year I got away with planting the seeds in early winter. Plant in moist, rich soil with good sun exposure, following the depth and spacing instructions on the seed packet.
Winter varieties of radishes grow more slowly and aren’t as likely to bolt as quickly other radish varieties due to the cooler growing temperatures. When ready to harvest, most radishes will bulge through the ground. If left too long to harvest, radishes tend to become pithy or spongy in texture and may develop a harsh flavor.
The Watermelon radish takes approximately 60 days to grow to maturity. I tried harvesting my watermelon radish at different sizes and noticed that the peppery flavor certainly varied with the harvest time, so it’s worth experimenting with the harvest. I left a few of my radishes in the ground longer than 60 days and they got quite large – up to 5” – and they were quite spicy (but not yet bitter) when I picked them. No wonder my children didn’t like them, but I sure did. Yum.
This “trial vegetable” was easy to grow and was a pretty, zesty addition to salads and other dishes. It has definitely moved from “trial” status to a regular rotation in my vegetable garden.