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Over the Garden Fence

Starting Flower and Vegetable Seeds

Last weeks' column briefly mentioned starting seeds for the flower or vegetable garden and that you need to start by reviewing the seed packet instructions. That is just the start of course of what will be a several week adventure.

For our area, May 5th has been the average frost free date for many years. If we are having an early spring, a few days earlier can work. With our weather being so abnormal, May 5th may be a better date this year for planting those very hardy seeds and transplants.

Based on the date you expect to plant, the information on the seed packet can guide you when you need to start your seeds. Seeding four to six weeks ahead is pretty common, yet be sure you follow the label. After reading all the seed packets, you will see that starting all your seeds at the same time is not the thing to do! Those warm loving vegetables can be sown later so they will not be overgrown and leggy by the time you will be transplanting them to the garden.

To avoid seed germination issues, use either clean or brand new seedling flats. Along with the seedling flats, use a soilless media to avoid soil borne diseases. Soilless media will also drain quickly while holding adequate moisture. While you are waiting to see the first signs of seedling emergence, make sure the soil media is kept moist but not overly wet. This can be just a matter of a few days to 10 or more days. Some gardeners will lightly cover the seedling flats with a sheet of plastic or saran wrap to conserve moisture and retain a bit of heat that may hasten germination.

Some seeds are happy to germinate in the dark while others require light. You may need to group those seeds in the same seed flat. Once the seedlings emerge, they all require light immediately. Light intensity drops off quickly the farther the light fixture s away from the flat. A bright indirect light from the sun in a window will work too. If the light source is too far away, the seedlings will stretch and end up leggy long before it is time to take them to the garden or flower bed. Your seedlings will also stretch if the night time temperatures are high, so that cooler window sill may be a better place.

Once you are getting closer to planting day, those transplants will need to be conditioned to the outdoors. Several days ahead of planting day, set them outdoors in a protected location a few minutes each day, extending the time outdoors each day. Try to pick a planting day where the weather is cooler and cloudy. This will be a better first day for the transplants than a sunny hot day. Watch them carefully to be sure the transplants do not wilt from lack of moisture. Their root systems are limited to the transplant container and can easily dry out.

About the author: Richard Hentschel’s expertise extends across several subject areas with specialties in lawn care, fruit tree production, woody ornamentals, and home and community gardening. During his 45-year career in horticulture and agriculture, Hentschel became a well-known and respected expert for commercial and homeowner audiences, industry organizations, and media. He retired from University of Illinois Extension in April 2022 with nearly 30 years of service as a Horticulture Specialist and Educator in northern Illinois.