Spring fever, gardeners? These simple steps will get seedlings off to a good start
The spring gardening season is getting closer with each passing day. Slowly the days are getting longer. This is the time of the year many of us are feeling the need to get our hands in the soil and see green. One way to scratch the itch is to start seedlings for planting in the garden.
The advantage of growing your own is getting a specific variety of vegetables or flowers. Growing your own transplants is easy when you follow just a few simple rules: using the right potting mix, providing ample light and timing the planting correctly.
Potting mix or soil used for growing seedlings should be very light and airy, yet able to hold water for even moisture. Potting mixes should be sterilized to reduce the chance of disease development. Commercial combinations are available at most garden centers. These mixes do not contain any soil, sand, silt or clay. They are made of shredded bark, peat, coconut coir, vermiculite or perlite.
The mixes have little fertility. Once the seedlings germinate, they need to be regularly fertilized to help grow a vigorous plant. The container used for seed starting should allow for good drainage.
When we were kids, we probably attempted to grow a seedling on the windowsill. The result, in most cases, was a spindly and straggly plant. The challenge with growing transplants is providing intense light levels for an extended period. High light levels are necessary for the desired short, stocky finished plants.
Shop lights that use either older fluorescent bulbs or newer LED lights are the best way to provide the intensity and duration of light needed. These light structures are lower cost. Transplants grown for a short period are not as picky about the wavelength of light.
The key to using lights is twofold. One is the intensity of light. Lights should be within a few inches of the tops of the growing seedlings. Lights placed further away will cause the seedlings to reach for the light. The light placement will need to be adjusted as the plants grow. Second, the lights should be left on for at least 16 hours per day or better yet, left on all the time. This combination of intensity and duration should result in a quality transplant.
The greatest challenge may be knowing when to start the seedlings so they are at their peak when it is time to plant outside. Most transplants require about 6 to 8 weeks to germinate and grow into a 4 to 6-inch plant with strong roots and leaves to grow outdoors.
Count backward from the recommended best planting date to know when to seed. For example, a tomato planted outdoors in mid-May will require planting seeds around mid to late March. Broccoli planted in the garden mid-March is seeded in late January or early February.
The rate of growth depends on room temperature. The average home room temps are usually best for plant growth.
Whether you are a seasoned pro or have not tried growing transplants, now is the time to scratch that gardening itch. There is nothing like the feel of the soil between the fingers and seeing green growth.
Dennis Patton is a horticulture agent with Kansas State University Research and Extension. Have a question for him or other university extension experts? Email them to firstname.lastname@example.org.