Seed Starting

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March 21 is behind us. It’s officially spring! Some warmer days and still cold nights, so it still may not feel like it yet, but gardeners are yearning to be outside and get their hands in the soil. With so much to get done, it’s easy to feel dazed on where to begin. With a bit of planning ahead and getting organized, spring chores can be a relief from the winter doldrums and not a burden. Start with the seeds you couldn’t resist buying from those catalogs that began arriving months ago.

Seed Starting

Since we start seeds of vegetables and annuals indoors 6-8 weeks before setting them out, now is the perfect time to get cracking on it. Make a planting schedule so that seedlings are mature at the optimal time for our area. Once soil temperature reaches 40 degrees F, crops such as greens, radishes and peas can be directly sown. Wait until soil temperature warms to 50 degrees F to plant vegetables like cabbage, onions and Swiss chard.

Starting garden plants from seeds indoors can be an enjoyable project for any gardener. I’ve put together growing shelves for this purpose. It works well and is a relatively inexpensive way to grow a wide variety of plants. A few things to keep in mind for this technique:  Choose a place that is safe from heavy traffic, pets, cold drafts, and excess heat. Set your shelves in a spot where spills of potting mixture, water, or fertilizer will not be a problem, where air temperatures are above 60°F and adequately warm if bottom heat is not provided. Most seeds need consistently warm soil to germinate and produce strong roots. Cooler soil temperatures can lead to seedling death due to disease.

Clear plastic domes that fit over trays of plants allow light in, but help keep moisture from escaping. It doesn’t have to be fancy. Look around for plastic containers, like cake or cupcake “boxes” from the grocery store. They will get provide the function you’re looking for. They can also help retain heat provided to the root zone. The domes should be removed when the seedlings are tall enough to touch them.

It’s much better to grow seedlings under fluorescent lights than to rely solely on natural light, even in a greenhouse. Some brands of lights are sold as “grow lights,” designed to provide light in specific ranges required by plants. Standard fixtures with two fluorescent tubes per fixture also give plants adequate light and are not expensive. Combining a “warm” white tube with a “cool” white in the same fixture will give the same results as a pair of special “grow lights.”

Since light intensity is reduced at each end of any fluorescent tube, longer tubes generally give you more useful light per foot. Keep the lights just 2 or 3 inches above the tops of the seedlings. Leave them on for 16 hours each day. A simple timer can be part of the setup to ensure lights are turned off and on automatically. When fluorescents are farther away, the energy reaching the plants is reduced. The seedlings will stretch toward the light and become leggy and weak-stemmed. Hanging the seed-starting lights on chains is one way to raise the lights as the seedlings grow by moving the chains a link or as needed to maintain the desired distance. Starting seeds indoors is smart and fun. It’s also a perfect opportunity to involve children in gardening – a hobby that will reward them for a lifetime!

Minda Daughtry is Horticulture Agent for North Carolina Cooperative Extension in Lee County.