10 top tips for growing root vegetables
GROWING CARROTS, BEETS, RADISHES or other root vegetables can be more challenging than, say, growing a zucchini or pole bean, but these long-storing staples are worth mastering. What’s the secret to growing root crops, whether the most familiar kinds, or even a turnip or parsnip?
1. Timing is everything: In general, says Daniel Yoder (above), a research product technician at Johnny’s Selected Seeds in Maine, root crops prefer to mature in cool weather. “Most of these crops grow and taste the best when planted in July or August for fall harvesting,” he says. “Plus, colors on the roots will develop more vibrantly in cool soils.”
Carefully choose your varieties for each season, sowing faster-maturing varieties for spring and slower-maturing varieties for summer plantings for fall harvest and storage.
2. Direct sow for success: Growing root vegetables can be especially challenging because they require direct seeding to grow strong, unhindered roots and some grow rather slowly from seeds, especially in cooler spring soils. Beets are an exception that can be transplanted, with care taken to get them planted at the right time. (Some farmers are experimenting with planting radishes, beets, and even carrots with the Paperpot Transplanter to give them a jump on the weeds.)
3. Don’t skimp on sunshine—select a full-sun location. Too much shade means your plants may struggle, and under-perform.
4. Don’t skimp on bed preparation, either. Loosen the soil, picking out rocks, says Dan, then firm the bed before sowing so that you’ll get good seed-to-soil contact.
“You don’t want to loosen it and just plant into a loose bed,” he says, “because that bed will settle a little bit, which will also distort the root growth a little bit and just set them back.” Many gardeners increase their success rate by growing their root crops in a raised bed, especially in areas with heavy soil.
5. Reduce potential weed pressure as you prep, to give your root vegetable seedlings the best chance, rather than forcing them to compete for space and resources. Solarizing or tarping the bed (how that works) is one organic tactic, or cleanly cultivating all weed seedlings for 2-3 weeks prior to planting. You may need to water once to get the weeds to grow.
6. Moisten the seedbed before sowing, then “provide low volume but frequent, even moisture through germination,” says Dan. “One big trick that a lot of people don’t think about is making sure you pre-irrigate your beds.” Some gardeners then cover the pre-moistened, sown row with row-cover fabric or even a piece of burlap or grass clippings to keep the moisture in while awaiting seedling emergence.
7. Spacing root vegetables is very important. “You don’t want to just put down a lot of seed because it’s quick and easy,” says Dan. “If you take a little extra time to put down closer to your appropriate spacing, it’ll save you way more time later on with the thinning process.” Some gardeners find pelleted seed (above) easier to space carefully.
8. For maximum yields, find varieties that tolerate crowding and give them more time to grow. “Some varieties of beets, radishes and carrots are genetically more tolerant to crowding than other varieties,” Dan explains. “‘Adelaide F1’ and ‘Yaya F1’ are examples of carrots that are known to be able to handle some crowding, for instance, but the closer the roots are together, the more slowly they will develop to a harvestable size, so be sure to give those time to grow.”
9. Thinning may be necessary to achieve correct spacing, as hard as we may try when sowing to follow packet recommendations. Dan usually waits to thin until root crop seedlings are big enough that he can easily grab them with his hand.
“I think rutabagas and turnips, in particular, are a little pickier,” he says, “and I wouldn’t wait too long on them because they really seem like they need their space to size up early.” Radishes and beets (above is ‘Zeppo’ beet), however, can be thinned as early as the first true leaf—and so can carrots, but that may backfire a bit:
With carrots and parsnips, because they can be slow to germinate thinning extra-early may mean not all the seedlings have emerged yet, so Dan waits until they’re a little bit bigger—even like 2 or even 3 inches.
10. Don’t let root vegetables dry out when they’re starting to swell. Consistent watering is important, too, as with most crops, but pay extra-careful attention when the roots are developing.
AGAIN: Root vegetables may be a little harder to get established than that tomato transplant, says Dan, but so rewarding to learn to grow.
“I feel that growing carrots and parsnips well is a real milestone for growers of all sizes,” he says. “It’s like digging for treasures.”