Extension Communications
3614 Administrative Services Building
Ames, Iowa 50011-3614
(515) 294-9915
2/19/01
Contacts:
Richard Jauron, Horticulture Extension, (515) 294-1871,
rjauron@iastate.edu
Elaine Edwards, Continuing Edudcation and Communication
Services, (515) 294-5168, eedwards@iastate.edu
Yard and Garden Column for the Week Beginning Feb. 23
Starting Impatiens from Seeds
By Richard Jauron
Extension horticulturist
Iowa State University Extension
Impatiens are excellent plants for those shady areas in the home landscape. Impatiens are ideal for flower beds, planters and hanging baskets. Their versatility and adaptability to shade have made impatiens the most popular annual bedding plant in the United States.
While impatiens are relatively easy to grow from seeds, they are slow growing. Home gardeners should sow seeds in late February to produce stocky transplants by spring. Suggested impatiens for Iowa include varieties in the Accent, Tempo and Super Elfin series. Plants in these series are compact, free flowering and available in a wide range of colors. Other suggested impatiens include varieties in the Carousel and Java series. Carousel impatiens produce double and semi-double flowers on compact, well-branched plants. Varieties in the Java series are seed-grown New Guinea impatiens.
Commercial soilless products, such as Jiffy Mix and Redi-earth, are good germination media. Containers used for starting seeds should be clean and have drainage holes in the bottom. Previously used containers should be washed in soapy water and then disinfected by dipping in a solution containing one part chlorine bleach and nine parts water. The chlorine bleach solution should destroy any fungi on the container surfaces that could attack and destroy the tender seedlings.
Fill the container with the germination medium to within 1/2 to 1 inch of the top. Level and gently firm the medium with a small, clean board, then moisten the mix by partially submerging the container in water. When the surface becomes wet, remove the container. The medium also can be moistened with a rubber bulb sprinkler. Bulb sprinklers emit a fine spray that won't displace the medium or seeds. Sow the seeds after the medium has been allowed to drain for 1 to 2 hours.
The seeds of impatiens are small, so sowing seeds can be somewhat difficult. A wooden toothpick can help simplify the sowing procedure. First, empty the seeds into a small bowl. Then moisten the end of the toothpick and touch a single seed with the moistened end (the seed will stick to the moistened toothpick). Place the seed in the proper location and press it into the germination medium. An alternate method is to sow the seeds by gently tapping the seed packet as it is held over the medium. The seeds can be pressed into the soil with a small board. Do not completely bury or cover the seeds. Impatiens seeds need light to germinate.
After sowing, thoroughly moisten the medium again. Allow the medium to drain for a few minutes, then cover the container with clear plastic wrap. Clear plastic domes also are available for standard-sized flats. Set the container in bright light, but out of direct sunlight. Extremely high temperatures may develop if the covered container is placed in direct sun. The temperature of the germination medium should be 70 degrees F. Higher temperatures may inhibit or prevent germination. The seeds should germinate in 14 to 21 days.
As soon as germination occurs, remove the plastic covering and place the seedlings in a sunny south window or under fluorescent lights. For best results, grow seedlings under fluorescent lights. Plants grown in a sunny window often get tall and spindly because of inadequate light. A standard fluorescent shop fixture with one cool white and one warm white 40-watt fluorescent tube works fine. The lights should be no more than 4 to 6 inches above the growing plants and should be left on for 12 to 16 hours each day. Transplant the seedlings into plastic cell packs, peat pots or other containers within 10 to 14 days of germination. To produce stocky plants, grow the seedlings at a temperature of 60 to 65 degrees F, keep them on the dry side and fertilize weekly with a 1/4 strength houseplant fertilizer solution.
Harden the plants outdoors for 7 to 10 days before planting them into the garden. Place the plants in a shady, protected area for 2 to 3 days, then gradually expose them to a small amount of sun.
Excellent quality impatiens can be purchased at garden centers, greenhouses and other retail outlets in the spring. However, growing your own plants from seeds is fun and rewarding.
ml: isugarden
Extension programs are available to all without regard to race, color, national origin, religion, sex, age, or disability.