As of Tuesday, January 27, 2015
When perusing spring seed catalogs, don’t pass on perennials. These long-lived plants require a bit
more commitment than annuals, but provide pleasure year after year.
“Annuals are essentially programmed to rush, rush, rush,” said Brooke Edmunds, horticulturist with Oregon State University’s Extension Service. “They grow, flower and set seed within the first season and are gone. Most perennials put energy into growing a strong root system and foliage before flowering the following year, but then last much longer.”
The same guidelines for starting annuals from seed apply to perennials, except that some varieties may need a period of chill, soaking, scratching, breaking or nicking of the seed coat. The back of seed packages will let you know if that’s necessary.
Germination is a key time for all types of plants, according to OSU Extension horticulturist Weston Miller.
“During this fragile time in the life of a plant, it’s critical that seeds receive appropriate amounts of water, oxygen and light,” he said. “At this point, starting seeds can become a balancing act.”
To get seeds off to a good start, make sure the soil mixture is light and fluffy. Buy a product made for seeds, Miller advised, and never use soil dug from the yard, which is too dense and could contain fungi that cause the common disease called damping off. Once seedlings are infected, they wither and die.
In addition to using good quality growing medium, it’s important to keep the soil from getting too wet or cold. For best results, grow seedlings in an area kept above 65 degrees, Edmunds said. Moisten the soil before planting and then water with a spray bottle frequently but not to the point of saturation. When the seedlings come up, use a water dropper or even a turkey baster to water.
Keep seedlings in a south-facing window or use grow lights hung within 2 inches of the plant, raising them as they grow. If in a window, turn frequently so starts don’t get leggy from leaning toward the light. Be sure to pinch out the smallest plants, leaving room for the strongest to thrive. Once substantial enough to plant outside, harden them off by taking outside for a few hours daily for a week.
“People may think that all seeds need to be started indoors,” she said, “but many perennials, such as viola, blanket flower, black-eyed Susan and sea thrift, can be directly sowed into the garden and you can skip that step altogether.”
Besides being easy to seed outdoors, blanket flower (Gaillardia aristata) is a favorite of Edmunds because it blooms the first year and sports attractive seed heads for winter interest. Black-eyed Susan (Rudbeckia hirta) appeals because of its prolific nature and the variety of colors available, from sunny yellow to butterscotch to red. Among her other preferred perennials is the easy-to-grow, vibrantly colored penstemon (Penstemon hartwegii) that’s irresistible to hummingbirds and the statuesque lupine (Lupinus).
Direct seeding perennials couldn’t be easier. Follow package directions for planting depth and spacing and keep moist, Edmunds said. She suggested using a light fabric cover to keep moisture in.
For more information, check out Extension’s guides to Producing Transplants at Home and Propagating Plants From Seed.