Released March 13, 2009
SEARCY, Ark. - For many gardeners, spring begins long before the thaw with a packet of seeds grown on a sunny windowsill, says Sherri Sanders, White County extension agent with the University of Arkansas Division of Agriculture.
It's easy for gardeners to get a head start on the growing season and pick up the habit. "Sowing seeds indoors is a simple technique," she says. "As long as you pay attention to light, temperature and moisture, success comes easy."
Sowing
As a general rule, sow seeds before indoors six to eight weeks before the last frost date. Smaller-seed annuals, such as petunias, snapdragons and begonias, need more time to reach transplant size. Many seeds come with their own planting advice. "Information on the seed packet is your best guide in knowing when to sow," says Sanders.
Make sure to time indoor plantings so seedlings don't outgrow their containers before it is time to transplant them out in the garden. Seedlings kept indoors too long will be weak, says Sanders. "They'll grow slowly and bloom poorly," she says.
Choose a container at least 2 inches deep with drainage holes when planting seeds. "A terra cotta or plastic pot works just fine, or a plastic growing flat or a clear-lidded deli container with holes punches in the bottom," says Sanders. Seedlings will be transferred later to individual pots, multi-cell packs, or peat pots directly in the ground.
Using fresh potting mix will help avoid disease problems, says Sanders. Maintain moisture by covering the seed-starting container with a clear plastic dome or bag. Keep the container in a warm location - about 75 degrees - to encourage quick germination.
Seedlings
Once the seedlings sprout, remove the plastic cover and move the seedlings to a cooler spot. This is necessary because of the effect it has on young plants. "The seedlings of many annuals grow best at around 65 to 70 degrees," says Sanders.
Sturdy, healthy seedlings cannot grow without bright light. "If you live where late winter days are often cloudy, even a south window may not provide enough light for your seedlings," says Sanders. Consider supplementing natural light with a fluorescent shop light, hung so the tubes are just an inch or two above the leaves.
When the seedlings have formed their second set of leaves, they're ready to transplant, says Sanders. "Don't delay too long in transplanting the seedlings or you'll find yourself ripping tangled roots," she says.
Growing from seeds may be a little more time-consuming, but it allows the gardener to reach beyond what's usually available.
"Your local garden center might offer three kinds of geraniums - red, salmon, and white - while a good seed catalog lists 20 or more," says Sanders. "And compared to transplants, seeds are a bargain."
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http://www.uaex.edu/news/march2009/0313seed_indoors.htm
Contact: Lamar James, (501) 671-2187, ljames@uaex.edu
