It certainly has been a long winter, and at times it seems like summer is never going arrive. Why not think green? Get a head start on summer gardening by starting your seeds inside. The variety of seeds available for home planting offers much greater variety than the everyday specimens you'll find in the garden centers. It's a wonderful opportunity to experiment with the latest hybrids and vegetables. Planting now will assure that you'll have an earlier harvest, and give you a longer growing season. Plus, you'll have the satisfaction of knowing that you raised the food you're eating from seed to table!

Where to plant

A windowsill might seem like a good place to begin seeds, but in these northern climates windows often get too cold at night, and too hot in the bright sun. As the sun moves throughout the day, the seedlings will tend to grow toward the light and become bent and spindly. Lighting from above will allow your plants to grow straight and upward. A grow light maximizes germination by simulating sunlight and will give your seedlings an additional boost. Your seedlings should receive 12-16 hours of light daily, plus a period of darkness in between. Keep the light between 2-4 inches above your seedlings, maintaining this distance as they grow. Choose a location in your home that doesn't have a lot of traffic, and gives you room to maneuver as your seedlings grow. A multilayered shelf works well, as well as plastic tables. If you have room, a portable greenhouse is a good choice, because it can be moved outdoors when the temperatures warm.

Choosing seeds and timing your planting

When selecting your vegetable and annual flower seeds, check the packets for the number of days until harvest and make sure those you choose will have enough time to ripen. Depending on the variety, you can start planting as soon as early February. Plants with long growing seasons benefit the most from being started indoors. The University of Minnesota Extension suggests the following timeline for planting common vegetables and annuals in the Great Lakes region:

  • - Plants requiring 14-15 weeks of indoor growing time: onion, leek, geranium, pansy
  • - 12-13 weeks of indoor growing time: celery, impatiens, stock, larkspur, lobelia
  • - 10-12 weeks of indoor growing time: broccoli, cabbage, head lettuce, coleus, snapdragon, petunia
  • - 9 weeks of indoor growing time: peppers, eggplant, sweet alyssum, hollyhock, dianthus
  • - 5-6 weeks of indoor growing time: tomato, aster, nasturtium, bachelor's buttons
  • - 3-4 weeks of indoor growing time: zinnia, cosmos


Plastic trays, wooden boxes, or other containers 2 1/2-3 inches deep are ideal for starting your seeds. There should be ample drainage in your containers. Make sure you have a tray underneath to avoid water for spilling on your tables and floors. A good seed-starting mix will contain all the nutrients needed for strong roots. Be sure to use a disease-free growing mixture, never soil your outdoor garden. Divided containers work best because the individual planters protect the seedlings and protect their delicate root systems from becoming entangled.

Onions and leeks are the exception—plant them in one large flat and transplant to garden when small. Fleet Farm carries a variety of seed-starting trays, from basic seed starting trays to greenhouse kits expressly made for starting tomatoes. Peat pots are excellent for vining plants, such as melons, cucumbers or pumpkins, because the plants can be sunk into the ground without disturbing the delicate roots. When choosing what to plant in your flats make sure that the growth rates and requirements are taken into consideration, and use different flats for plants with different needs. Plant seeds as specified on packets (generally 2-3 times deeper than the seed's diameter). If using a tray with individual compartments, place 2 seeds in each one, then cover with growing mix. Prevent the seeds from washing away by using a spray bottle, or by placing the container in a shallow pan (or the bathtub) so that water soaks in from the bottom.

After planting, cover the container to prevent the seeds from drying out. If your tray did not come with a domed lid, use clear plastic or paper on top to keep the plantings moist. A warm heat from underneath will help prevent rotting (a problem called “damping off").Heated mats are available to help provide a low, steady heat while your seeds are germinating. Once seeds have sprouted through the soil, remove the cover. Maintain adequate watering (but don't overwater) and give them12-16 daily hours of light.

As your seedling grow, you may have to transplant them to larger containers. You can use peat pots, or recycle your plastic yogurt containers and cups by punching drainage holes in their bases. Fill the containers ¾ of the way with planting mixture. Use a spoon to carefully lift the seedling out of their original container. Move to the new container, taking care not to crush the stem. Add soil around the seedling, press around the roots, water and move back under the light.

Getting ready to go outside: Hardening off

Because your seedlings have not been exposed to wind or full sun and fluctuating temperatures, you'll need to gradually expose them to the elements. This “Hardening off" process will let them get accustomed to their new environment and prevent them from wilting or death. Two-three weeks before you move them outdoors, move your plants outside for a little bit of time each afternoon. Choose a protected, shady spot and bring them back inside before temperatures drop. Each day, leave them out for a little longer, and gradually move them to areas with more sunshine. At the end of a few weeks, the plants will be ready to stay outside until you're ready to transplant them in the garden or flower bed. It's best to transplant them on a cloudy or overcast day, to avoid wilting in sudden exposure to bright sun.