STARTING SEEDS INDOORS…TIMING IS EVERYTHING

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Many plants can be started indoors, but like planting outdoors, timing is everything. If you plant outside too early, you can loose your new seedlings to frost. When you push the season indoors, you’ll be struggling to keep your seedlings growing strongly until it’s safe to set them out.

The proper time for sowing seeds for transplants depends upon when your plants can safely be moved outdoors. Check the date of your last frost, then count backwards four to six weeks, depending on the plant’s germination rate and the outside growing conditions the plant will require to thrive. For example, the minimum soil temperature for tomato growth is 50ºF to 55ºF. Planting tomato or other warmth-loving seedlings outdoors before the air and soil temperatures warm up will not give you earlier harvests, rather unhappy plants that will be overtaken by plants set out later under favorable conditions.

Once you’ve chosen the best time to start your indoor seedlings, the second most important choice is where you’ll place them as they grow. Your biggest challenge is light. Seedlings need a lot of light. When they don’t get enough, they become tall, and "leggy.” After your seeds germinate, place your seedlings in a south-facing window if possible.

If you’re not fortunate enough to have a large, bright window, you’ll need to provide some supplemental light. Two 40-watt fluorescent tubes, one cool white and one warm white will provide a good balance. Position the plants 6 inches from the tubes and keep the lights on about 16 hours each day. As the seedlings grow, the lights should be raised.



There are many choices for containers to use for starting seeds. I like to use containers that can be planted directly in the ground when your seedling is ready to set out. For example, you can make your own little starting pots from newspaper. Or there are compressed peat pellets or pots. You can also use recycled plastic containers such as yogurt cups. If you choose a rigid container, make sure you’ve provided ample drain holes.

After selecting a container, fill it to within 3/4 of an inch from the top with moistened sterile medium. For very small seeds, at least the top 1/4 inch should be of a fine, screened mix or a layer of vermiculite. Firm the growing medium into your containers. Sow the seeds thinly and uniformly. Lightly cover the seed with dry vermiculite or sifted medium if they require darkness for germination. A suitable planting depth is usually about twice the diameter of the seed, but check the manufacturer’s instructions.

To maintain moisture, slip the whole flat or pot into a clear plastic bag after the initial watering. The plastic should be at least 1-1 1/2 inches from the soil. Keep the container out of direct sunlight otherwise the temperature may rise to a point harmful to the seeds. When your seeds germinate, remove the covering and keep them uniformly moist, but not wet.



When the seedlings are tiny, keep them in indirect bright light. Direct sunlight through glass can be too intense. As they grow and develop their first set of true leaves, you can move them directly to a sunny window. Then just keep them gently watered, and enjoy the amazing sight of a tiny dry seed unfolding into a growing, green miracle.


Next: Hardening off your plants