Picking a plump, juicy Heirloom or Better Boy from your own summer garden brings immense satisfaction. For those getting ready to start tomatoes and other garden picks from seed, a Virginia Cooperative Extension agent offers some advice.
“If you want to grow your own tomatoes from seed, they should be started six to eight weeks before you want to plant them outdoors,” says agriculture natural resource extension educator Kirsten Ann Conrad.
You can use seedling trays, but she says they will need to be replanted multiple times. “Very quickly, if they are healthy, they’re going to outgrow that space,” Conrad says.
Your potting mix should be pasteurized, fine in texture, and drain well. The pots need to be clean. “We recommend if you’re reusing pots or growing containers for indoor plants that you wash them in a mix of 10 percent bleach solution to be able to kill off any kind of pathogens,” she says.
“You can’t have a big coarse potting mix with the little, tiny seeds because the seeds have to remain in contact with the moisture while they are germinating,” she says.
The grow lights you use need to be no more than 6 inches from the top of the plants and stay on for 14 to 16 hours a day.
“The lights are very, very important. Folks don’t realize how much light they need to have to start the seedlings and to produce a fine plant to put outside,” Conrad says. “You want a sturdy plant to put outside, and you’re not going to produce that simply by growing these seedlings in a sunny window.”
Use a heating mat to keep the soil warm and remember to water to avoid wilting. “If they wilt, you should throw them away and start over again. Wilting damages the ability of the plant to take water up from the roots,” Conrad says.
But don’t overwater, or your plants could get damping off, a fungal disease that attacks young, growing seedlings at the base of the stem.
Tomato plants need to reach 6 to 10 inches in height before you replant them outside. Replanting shouldn’t happen until the outside soil temperature reaches at least 65 degrees. Typically, there is a “window of opportunity” for replanting between the end of April and May 20, Conrad says.
Her tip for planting tomatoes outside: Plant them deeply and sideways, up to the first set of leaves. “The stem you are burying will produce more roots, and the plant will be stronger for it.”
DIY Soil Recipe
Virginia Cooperative Extension agent Kirsten Ann Conrad says this would be a soil mix that you could use when transplanting plants to larger containers.
- 1/3 part sphagnum peat moss or coco coir fiber
- 1/3 part finely screened compost
- 1/3 part vermiculite
For low-level nutrients, add about 1 to 2 cups of worm compost to a 5-gallon bucket of your soil mix.
You can also stretch commercial potting soil by adding up to 50 percent screened compost when transplanting seedlings into larger pots.
Feature image, stock.adobe.com
This story originally ran in our March issue. For more stories like this, subscribe to Northern Virginia Magazine.