Use idle grow lights to grow salad greens indoors

To beat the winter doldrums, we’re doing some indoor gardening on a small scale this winter, without a greenhouse. We decided instead of letting our grow lights that we use for seed starting just sit there in storage doing nothing, we’ll put them to use growing salad greens.

Back in late-October, we sowed a variety of seeds into seed-starting containers. Then in mid-November we transplanted the resulting seedlings into flat plastic crates and seed starting trays.

The crates are quite a bit deeper than seed starting trays, which allows for a larger volume of soil for plant roots to grow, which works out great since we wanted to grow radishes along with the greens.

The growing medium we are using is just some bagged potting soil that we had left over from last season.

Since the bottom and sides of the crates have slotted openings, we lined the crates with newspaper to keep the soil from sifting through. I keep telling everyone that paper print newspaper has dozens of uses in the garden making it another good reason to get a subscription for home delivery; but I digress.

Because there’s not much soil to hold moisture, the shallow seed starting trays tend to dry out faster than the crates. That hasn’t been too much of a problem since our growing rack is in our semi-heated garage, which stays around the upper 40s to lower 50s degrees Fahrenheit this time of year. As long as they’re kept watered, the shallow trays works just fine for leaf lettuce as the roots spread sideways in the trays.

The plants are getting a shot of half-strength soluble fertilize every other week or so since that is the only source of minerals that they’ll get. Peat based planting mixes contain very few minerals so fertilizers are required to keep the plants growing.

Standard florescent tubes give off a small amount of heat, that seems to be just enough warmth for the cool weather crops we’re growing.

While florescent tubes can provide enough light to support photosynthesis, they must be very close to the growing plants in order to be effective, within an inch or so from the top leaves of the plants.

The lighting schedule I’m following is: lights on 24 hours a day for two or three days straight; then turn off for one night; and back on the next morning continuing the cycle.

During the last couple of weeks we’ve been picking leaves from lettuce and kale for small salads making sure to leave enough leaves on the individual plants so they can produce energy to keep growing.

The greens are tender and mild tasting, not really needing a salad dressing.

Right now the radish roots are starting to swell and turn round. A few will be ready to harvest in the next week or two. As a bonus, radish leaves grown like this are very tender and make a great salad green as well.

If you want, you can certainly get out your seed starting lights and start growing some of your favorite salad greens now since we have several weeks of growing time before it’s time to start seeds for transplants.

Even if you don’t get large plants, you’ll still end up with micro-greens. Because the young plants grow and develop in soil, they will extract minerals from the fertilized soil mix making them much more nutritious and tastier than plain sprouts.

By using your seed starting equipment like this you are not going to end up harvesting a huge amount of produce but it will go a long way to help soothe the gardening itch that gardeners get at this time of year.

There are only 18 weeks to go until Mother’s Day, the target date used in southeastern Michigan for planting outdoor vegetable and flower gardens.