December 12, 1997

When do you feel the gardening season has really started? Is it when you can sow that early bed of peas, once the ground has thawed? Or is it a bit later, when cool-season vegetables like carrots and lettuce can be put into the ground? For me, it's no longer either of these. My gardening juices start flowing in early January, when I begin sowing vegetables indoors.

Many of us are used to starting tomato and pepper seedlings inside. Well, it's just as easy to jump start your spring garden. Of course you don't want to try carrot transplants (because of their taproot, just in case someone is wondering), but most of the other vegetables do quite well with a head start. Indeed, spring vegetables are probably much easier to raise indoors. For one thing, they are more forgiving of cold temperatures. Also the potting soil doesn't dry out as fast at these cooler temperatures.

The main concern is meeting your plants' light requirements at this time of year. If you have a sunny south-facing window that may be adequate, but I recommend getting a shoplight fixture (or two or three), and hanging it above a shelf such that the light will be no more than 4-5 inches above the tops of your plants. Most vegetables grow fine under a couple of shoplight tubes, which only cost a dollar or two apiece. I've found I get better plant color and development, though, if I use one 40W aquarium/plant tube ($8 each) and one 40W residential tube ($2 per bulb) in each fixture. If you mix florescent tube types in a single fixture, be sure they are both the same wattage! Most new shoplight tubes are only 24W.

I generally don't start these plants in a flat. Instead, I sow a few seeds directly into a 4-inch pot, and thin down to one plant once it has a couple of true leaves. This means my plants only get transplanted once, when it is time to go into the garden; so they get off to a faster start. Using this method also allows me to successfully transplant spinach, which can be touchy because of its taproot.

Some easily started spring plants are lettuce, spinach, chard, beets (yes, they have a taproot; but the beet forms up at ground level), mustard, and onions. Spinach, mustard, and onions tend to be photoperiodic, which means they will make a seed stalk if the daylength (even the "virtual daylength" under your lights) is too long. Because of this I have my growing lights on a timer, which is set to about 14 hours of "on" time.

To know when to sow these seeds indoors, follow the same rule of thumb you use for tomatoes and peppers. Sow the seed 6-8 weeks before the plants can safely be put outside. Here in western Washington these spring vegetables are usually safe outside after March 1st, so I sow the seed into the pots during the first half of January.

Given that these plants will be set outside while it is still rather cool, it is best to grow them under somewhat cool conditions so they won't be too shocked when you put them outdoors. An unheated garage or porch is ideal, as long as it doesn't get too cold! I have my plant starting area on my back porch, where it doesn't freeze unless the outside temperature gets down into single digits. This does mean, though, that you may have to provide extra heat so the seeds will germinate quickly. I use a heating mat placed on the shelf under my lights. You can also put the sown pots someplace warm, like the top of your water heater (or just inside your house). Just be sure to get them under the lights as soon as they start to germinate.

Under cool conditions the plants will grow somewhat slowly, so cut down the amount of fertilizer you provide. I use a bit less than 1 teaspoon of Rapid-Gro 20-20-20 in one gallon of water, and use that every time I water the plants (which is only about once a week in January).

All contents © Travis Saling
This page was last updated November 18, 2013