The winter winds may howl and the snow may fall, but gardeners can find solace in seed catalogs as they dream of spring.
“Starting plants from seeds gives such a feeling of accomplishment, not to mention that you can get a much wider choice of varieties when you grow from seed,” said Diane Blazek, executive director of the National Garden Bureau based in Downers Grove, Ill. “Starting from seed can give you bragging rights on uniqueness and certainly more variety for your garden.” And it can save you some big bucks. A 1-gallon pot of purple coneflowers, for example, can cost $8 to $10. A packet of seeds can provide dozens of the same plant for about $3.
“It’s great to start perennials from seed because you can grow many more plants inexpensively,” garden writer C. L. Fornari said. “You just need to be willing to start with small plants.” She grows thyme and other ground covers from seed for her expansive, colorful garden, called Poison Ivy Acres, in Cape Cod, Mass.
Many plants can be grown from seed indoors while others, such as beans and squash, are sown directly in the garden when warm weather arrives. But it might be worth it to start some familiar self-sowers from seed indoors.
“I used to grow zinnias from seed sown directly into the ground,” Fornari said, “but where I live the spring weather can be so cold and damp that they sometimes rotted.” Now she starts them indoors and transplants them.
Timing is important. You don’t want to sow seeds too early and end up with spindly plants on your windowsills because it’s too cold outdoors to put them in the ground.
“Determine the last frost-free date in your area,” Blazek said. “This is important because during our long northern winters, we get way too eager for spring and then may start the seeds too early. This results in leggy or diseased plants that won’t be as successful in the garden.”
For example, if you want to get a head start growing Little Firebirds nasturtiums, the seed packet from Renee’s Garden states that the seeds should be sown three weeks before the last average frost date.
What you’ll need
To grow seeds indoors, you’ll need a seed-starting or soil-less potting mix. Heavy garden soil is not recommended - it can contain diseases and doesn’t provide good drainage for the roots of tender seedlings. A container - even a clean milk carton - will work, as long as it has drainage holes in the bottom and a tray to catch the water. Moisten the potting mix so it’s slightly wet and place it in the container before sowing the seeds.
Read the seed packet carefully; it will contain the information you need for a successful trip from home to garden. For starters, follow the seed packet instructions for planting depth. If the seeds are planted too deeply, they won’t sprout.
“Light is important, too,” Blazek said. “Once the seeds germinate, you need the right amount of light, but not too much.” A bright, sunny window often will suffice, but placing the pots under grow lights (available at garden centers, home improvement stores and online) provides more consistent, even lighting. Winter sunlight is not as strong as in the summer, and there’s always the chance of dull, cloudy days.
Some seeds, such as sweet peas, morning glories and nasturtiums, have hard seed coats that hamper the seeds’ ability to obtain moisture and slow germination. To speed things up, scratch the surface of the hard shell with a nail file or sandpaper or soak the seeds for an hour before planting. (Again, this information should be on the seed packet.)
Most seeds germinate best if the pots are covered loosely with a sheet of plastic wrap. If you are growing the seedlings in a sunny window, remove the wrap during the day to prevent excess heat. After the seeds germinate, place the container in a cool, bright, well-ventilated area.
A tray of seedlings is a starting point. When there are too many seedlings in one pot, use scissors to snip off the weakest growing plants at the soil level. Eventually, most seedlings will need to go into larger pots before heading outside. When transplanting, handle the plants by the leaves, not their delicate stems.
Blazek moves seedlings from under her basement grow lights to a screened-in porch, then outside during part of the day until it’s time to transplant - a process called “hardening off.” This acclimates the still-tender seedlings to lower temperatures and stronger sunlight. Place them in an area protected from wind and direct sunlight for a few hours each day. Gradually increase the amount of time they are outdoors and keep an eye on them.
“A strong wind or hard rain can really damage young plants,” she said, and recommends transplanting outdoors on a spring day that’s not too hot, not too cold and not too windy. Keep the newly planted seedlings watered.
“There is nothing more life-affirming than taking your morning coffee to the garden or indoor seed-area and checking every morning to see which seeds have sprouted,” Fornari said.
For the gardener, it doesn’t get better than that.
Look for seed packets at local garden centers and online. Here are some for starters:
Territorial Seed Co., (800) 626-0866
Renee’s Garden, (888) 880-7228
Johnny’s Selected Seeds, (877) 564-6697
John Scheepers Kitchen Garden Seeds, (860) 567-6086
A helpful guide, titled “Starting Seeds Indoors,” is offered by University of Minnesota Extension, Go to extension.umn.edu/garden/yard-garden/flowers/starting-seeds-indoors.