Growing Indoors Requires a Fertile Mix of Care, Gear

The first steps in growing garden seedlings indoors are planting the seeds and getting them to sprout.

Start by gathering together a few plastic seedling flats or flowerpots and some potting soil. For potting soil, either buy a bag of packaged potting soil, adding extra perlite for aeration, or make your own by sifting equal parts garden soil, peat moss and perlite together through a quarter-inch mesh. Fill the flats or pots with moist potting soil, firming it just enough so that no large air pockets remain.

Either spread seeds over the surface of the soil or sow them in furrows made with the point of a pencil or row marker. Because conditions needed to sprout a seed are different from those needed by growing seedlings, and because different kinds of seeds vary in how long they take to sprout, sow only a single kind or ones with similar germination times in a flat.

After sowing, cover the seeds to the depth indicated on the seed packet, or use the general rule of burying a seed twice its thickness. Firm the surface after you sow the seed to establish contact between the seed and soil.

Now the flats need a thorough watering. Fill the kitchen sink or a basin with an inch of water and set the pans in the water for an hour. After removing seed flats from the water, cover each with a sheet of plastic or glass to hold in moisture.

All the seeds now need is a little heat, and possibly light, to speed germination. About 70 degrees Fahrenheit is an ideal temperature for getting most seeds to sprout. You can buy a thermostatically controlled heating mat made expressly for this purpose, or improvise by using the top of your water heater, your gas stove’s pilot light, or a warm spot.

Some seeds, especially tiny ones like those of snapdragon, lobella, petunia and hollyhock, also need some light to germinate. Large seeds, such as calendula and nasturtium, generally germinate best in darkness. Germination of most seeds, though, is unaffected by light, and even seeds that are affected are somewhat flexible, influenced by temperature and other environmental factors. Cover flats of seeds needing dark.

Finally, wait and watch for sprouting. Once sprouted, all seedlings need abundant light and slightly cooler temperatures.