Some gardeners are a little intimidated by the thought of starting plants from seeds indoors under lights. But that doesn’t mean they can’t grow their own plants from seed.
Many vegetables and flowers, especially annuals, do just fine sown directly into the garden, and some prefer it. And by sowing seeds into prepared garden beds, instead of buying whatever plants are available at a garden center in spring, gardeners can not only save money but choose from a much greater variety of flowers and vegetables.
Of course, you have to pay attention to the cultural requirements of the seeds you choose. Seed packets should tell you what you need to know – at what temperature it’s safe to sow the seeds outdoors, whether they need light to germinate, how long they’ll take to germinate, the number of growing days they’ll need to reach maturity. Make sure you choose vegetable varieties that suit the length of your growing season – you want to be able to harvest your crop before end-of-season frost arrives. For gardeners in many regions, that means you probably won’t be able to direct-sow edibles that demand a long, warm growing season, such as tomatoes and eggplants.
(If you aren’t sure what your frost dates are, call the extension service in your region, or a local public garden or nursery. To find out your hardiness zone, check out the National Arboretum’s Plant Hardiness Zone Map on the U.S. Department of Agriculture’s web site.)
Garden beds used for direct sowing should be well-prepared, with fine soil enriched with compost and no weeds or large stones. Seeds can be broadcast freely or planted in rows, depending on what plants you are growing and your garden design. If they need light to germinate, seeds should not be covered with soil or growing medium. Some hard seeds benefit from scarification, which means scratching the seed coat with a nail file or sandpaper to hasten germination. All seeds should have good contact with the soil, so tamp it down gently after sowing (some gardeners recommend using a flat board to tamp down larger areas). Soil should not dry out – keep it moist, but not soggy, and water with a gentle spray to avoid disturbing the seeds.
After seeds germinate and the plants develop their first true leaves, thin the seedlings as the packet directs. Don’t be tempted to leave all the seedlings in the bed, thinking you’ll get more for your money; only with sufficient space will individual plants grow strong stems, leaves and roots to produce flowers and vegetables.
Generally, the best seeds to grow directly in the garden are large seeds, because they are planted deeper and are tough enough to survive in outdoor conditions, or seeds of plants with deep roots. A variety of vegetables, including beans, peas, zucchini, carrots and most root crops such as turnips, beets and radishes, leaf lettuce and other leafy greens such as spinach, Swiss chard, and kale, are easy to grow outdoors from seed. So are numerous annual flowers, from sweet peas, marigolds, impatiens, foxglove, cleome, cosmos and forget-me-nots to plants that are harder to find at most garden centers, such as Amaranthus caudatus, the old-fashioned favorite with a romantic common name, love-lies-bleeding.
Root crops, especially carrots, are best grown directly in the garden, says award-winning vegetable grower Jeffrey Clarke, a horticulturist and educator at the Camden Children’s Garden in Camden, N.J. Carrots don’t transplant well, and if you start them indoors, their roots may bend at the bottom of the shallow containers, “and you won’t get a nicely formed carrot,” he says.
Potatoes, on the other hand, are tough. Just cut chunks of potato containing at least one eye, and bury the pieces a couple of inches deep, says Bill Rein, Burpee’s horticulture manager. He also suggests deadheading the flowers on root crops so that the plant’s energy goes into growing better roots – the part you’ll eat.
How heavily should you sow seeds outdoors? Keep in mind that not all seeds germinate, and some may be eaten by birds or other creatures, or washed away by rain. Most seed packets will give you guidelines, but opinions differ among seasoned gardeners. Rein prefers to sow thinly in rows, so that thinning those tiny seedlings is less of a chore. Clarke opts to sow more heavily than the seed packet directs, to allow for seeds that won’t germinate and other losses, and then he thins back to the recommended spacing. That way, he says, “you get a nice even row, and more yield for your space.”
As your plants grow, don’t be tempted to reach for the pesticides at the first hint of a pest. Instead, try more benign control methods. Learn which bugs are beneficial and which are truly pests, and how you can help cut down the numbers of bad bugs.
“One of the main problems with growing potatoes is defoliation by potato beetle larvae,” says Rein. “In a backyard plot, you can walk through the rows once a week and turn the leaves over to check for bright orange larvae, which are the eggs. Pick off the leaves with the larvae and dispose of them safely – not in the compost pile – and you shouldn’t have much of a beetle problem.”
Most of all, enjoy your garden. It can be fun to experiment with unusual varieties of seeds, whether your goal is to tempt your taste buds with exotic vegetables, or to delight your eye with unusual flowers.