If you’ve got spring fever, one great remedy is to start some seeds indoors. Have fun and get a head start on the gardening season when you sow and grow seeds indoors.
The easiest vegetables to start indoors from seed include broccoli, cabbage, cauliflower, eggplant, kale, peppers, and tomatoes. It's also easy to start lettuce, squash, melons, and pumpkins, but seeds sown directly in the garden grow so quickly that they often catch up with transplants. The easiest flowers to start indoors include cosmos, coleus, nicotiana, marigolds, sweet alyssum, and zinnias.
It's important to have seedlings the right size at the proper time for planting outside. Find out the last frost date in your area from your local Extension Service, then check the seed packet for information on how many weeks before that date to start seeds indoors and when it’s safe to set plants outside.
Containers, labels, growing mix—and of course seeds—are the essentials for getting started. Containers can run the gamut from purchased plastic flats and cell packs to peat pots to recycled cottage cheese cartons. Just be sure that whatever you use is sturdy and, most important, has drainage holes. Labels are important for keeping track of what’s what. Use a permanent marker to note the seed name and date of planting. While not absolutely necessary, a seedling heat mat will speed the germination of many kinds of seeds. And while a sunny windowsill may provide adequate light, you’ll get best results if you invest in fluorescent grow lights to provide additional illumination.
Seeds need a good disease-free growing medium. Start with fresh, sterile mix made for seed starting. These mixes are fine textured so small seeds can be planted at the proper depth. Moisten the mix before filing containers.
Planting depth is important. Some seeds need light to germinate and should be left on the surface. Read the seed packet for information on correct planting depth. As a general rule of thumb, plant seeds at a depth that's two to four times their width.
Seeds need moisture to germinate. If the seedlings dry out during the germination process, even briefly, they will die. If the seed starting mix is getting dry, gently mist the surface to rewet it. After seedlings germinate, keep the soil moist, but never soggy. Set the container in a tray of tepid water just until the surface of the mix is moistened as water is wicked up through the drainage holes, then remove it from the tray.
Finally, seedlings need nutrition. Once they get their first true leaves, begin to fertilize them with a soluble plant food diluted to half strength once or twice a week.