The following 101 on growing radishes comes from HOMEGROWN member Marianne, a.k.a. Mary, a dirt-under-her-fingernails city slicker and seed supplier from the Sunshine State. For more tips on planting, growing, and beyond, visit her blog, Back to the Basics. Thanks, Mary, and please keep the good ideas germinating!
The German giant is my favorite variety of radish. (That's it in all its glory, over there to the left.) It's not fancy or hard to grow, and it tastes great at any size. Radishes in general may be a cool-weather crop, but I continue to have success with them, even in South Florida. Need radish seeds? Peruse a list of HOMEGROWN’s favorite suppliers.
You’ll want to find a spot for your radishes in full sun or partial shade. Radishes prefer a soil pH of 5.5 to 6.8 and like loose, well-drained soil. Before you plant, make sure to add some organic matter (I like aged compost) to your beds and remove any lumps, roots, or rocks.
Sow your first crop of radishes two to three weeks before the average last spring frost date. (To determine your last spring frost, check out this chart from The Old Farmer’s Almanac.) You’ll want to sow the seeds ½ inch deep and 1 inch apart; thin successful seedlings from 1 to 4 inches apart in wide rows. For succession crops, sow every two weeks in spring and in autumn. Radishes require 22 to 70 days to mature, from sowing to harvest.
WEATHER, WATER, ETC.
Warm weather can result in small roots, and long days may cause radishes to bolt, so your best bet for planting is during the shorter days of spring and autumn. In mild winter regions, you can even grow radishes in late autumn and early winter.
Keep radish beds moist but not wet. Restrained but regular watering will result in quick growth. Radishes that receive too little water will become woody tasting. At midseason, side dress radishes with more aged compost.
Great companion plants for radishes include cucumbers, lettuce, nasturtiums, peas, and peppers.
Radishes can be grown in containers, as in the photo at right. To do so, sow radishes at least 6 inches deep in round containers, planting in concentric circles. If the weather grows warm, move your containers to the coolest location available.
MORE THINGS TO GROW
• From HOMEGROWN member Lucy: Growing Lettuce 101
• From High Mowing Organic Seeds: Growing Garlic 101
• And from HOMEGROWN: Growing Sprouts 101
Got a question for Mary about radish varieties? Or a radish-raising tip to add? Post it below and keep the conversation rolling. You can dig up more things to sow early and often in the Fall Planting and Winter Planting 101s, and you can always find more things to plant, grow, make, craft, cook, preserve, and water in the HOMEGROWN 101 library.