Buying seedlings from your local plant nursery is an easy and often affordable way to get a jump on the growing season. Growing plants from seedlings can be a desirable alternative to sowing from seed, which often requires more time and planning. That said, some plants have a more successful growth rate when they’re direct-sown. Transplanting seedlings into the ground from the containers they’re sold in can shock certain plants and inhibit growth. Ahead, we’re sharing the plants gardening experts say you should never buy as seedlings.
- Damon Abdi of the Hammond Research Station at Louisiana State University’s AgCenter
- Natalie Crist, a New York Botanical Garden-certified sustainable garden designer
Sunflowers
Sunflowers (Helianthus annuus) grow rapidly and look beautiful in mass plantings. “With so many varieties to choose from, having variations in height and appearance can create unique compositions in the garden,” says Damon Abdi of the Hammond Research Station at Louisiana State University’s AgCenter.
But they are better grown from seed rather than seedlings. “With a prominent taproot, direct seeding may be better to avoid disturbing taproot development and damaging growth,” says Abdi. As the seedlings break through the soil, thin them out to ensure the sunflowers have enough room to grow.
Cucurbits
Cucurbits, including squash, melons, cucumbers, pumpkins, and gourds, develop a primary taproot that transitions into a sprawling fibrous root system as they grow. “While they don’t rely solely on a single, deep taproot, they are still very sensitive to root disturbance when young,” says Natalie Crist, a New York Botanical Garden-certified sustainable garden designer.
Because cucurbits grow so quickly, they require uninterrupted root expansion to establish properly, Crist says. Transplanting seedlings often causes shock due to changes in soil conditions, moisture levels, and increased sun exposure, which can be stressful for fast-growing plants.
Snow Peas
Crist also always direct sows snow peas (Pisum sativum) rather than buying and planting them as seedlings. “They have shallow, delicate root systems that don’t respond well to disturbance,” she says. “Peas also develop nitrogen-fixing root nodules, which, if disrupted, can reduce the plant’s ability to absorb nutrients. I have never seen a transplanted pea seedling outperform one sown directly.”
Pole Beans
Pole beans (Phaseolus vulgaris) grow very quickly and are a great choice for direct sowing. “If growing seedlings to transplant, be wary of transplanting too late in development and potentially damaging the roots,” says Abdi. “With pole beans grown around a trellis, direct seeding can allow the plant to develop in place and for new tendrils to find their natural footing.”
Corn
Corn (Zea mays) is an easy plant to seed in the ground and thin out later as the seedlings emerge. “Corn shows signs of transplant shock if moved, leading to smaller plants that take time to recover (if it recovers at all),” says Abdi. “With the ease of growing corn directly from seeds in the ground, it makes more sense not to transplant corn.”
Carrots
Carrots (Daucus carota) have a central taproot, the plant’s desired part. It’s better to grow this vegetable from seed rather than transplant it because transplanting increases the risk of damaging the taproot. “Transplanted carrots may show signs of misshapen taproot growth that may make them less appealing,” says Abdi.
Radishes
Like carrots, radishes are tap-rooted plants that don’t respond well to transplanting. “Although taproots appear large and sturdy, they have a smaller overall surface area compared to fibrous roots, making it more difficult for them to reestablish,” says Crist. “If you purchase a tap-rooted plant from a nursery and its root is damaged or curled inside the pot, it will likely struggle to anchor itself properly.”
She adds that this also applies to beets, parsnips, and turnips. These tap-rooted plants are happier when they can spend their lives in one place undisturbed, Crist says.
