Gardeners advised to toughen up seedlings for spring planting

Now that it’s officially spring, gardeners who started their own transplants from seed over the winter are thinking about putting them in the ground.

In light of recently fluctuating temperatures, Virginia State University Small Farm Outreach Agent Susan Cheek is urging gardeners to take time to “harden off” their transplants. It’s important, she explained, to protect tender seedlings from frost damage by bringing them inside.

“For about two weeks, you should take your seedlings outside in their trays so they can get used to the wind and the rain and cooler temperatures, then bring them back in at night,” Cheek suggested.

“Even if you get plants from a garden center instead of raising them yourself, I’d harden them off at least one week before you put them in the ground.”

If the seedlings are cold-hardy plants like broccoli or cabbage, they can be put in the ground before the anticipated last frost. But if they’re summer vegetables or flowers, growers should wait until after the average last frost date to transplant.

That date varies across the state—as early as mid-April in Southeast Virginia and as late as late May for mountain elevations. Consult your local Virginia Cooperative Extension office, or use guides from the National Weather Service at weather.gov/rnk/frostfreeze.

Once soil temperatures are warm enough and gardeners are ready to transplant, they often face the challenge of root-bound seedlings.

“That’s easy to fix,” Cheek remarked. “What I would do is just take a knife or your hands, and break that root system up a little bit before you plant it. That will give it a chance to stretch out a bit and grow the way you want it to grow when you put it in the ground. It won’t hurt the roots a bit.”

Whether you put your transplants into the ground or in a large container, they’ll need plenty of water to help them successfully transition.

Cheek offered her advice on the March edition of “From The Ground Up,” a gardening segment on Real Virginia, the Virginia Farm Bureau Federation’s weekly television program. The episode is available online at youtu.be/FTGU March 2017.