There may be snow on the ground, but it is time to start thinking about gardening. Seed starting is a great way to get your gardening fix at the end of a long winter. Before doing so, take the time to plan out your process so you have the best success possible for your efforts.
Whether flowers, vegetables, or herbs, consider these factors before investing in planting seeds.
Read the seed packet and the description of the seeding requirements
The information you need for a successful planting should be on the back of the seed package. It will tell you how long germination takes, how long till ready to transplant, and what, if any special conditions are needed. Read carefully; some seeds require light to germinate and should not be covered with soil. Others require darkness, and may germinate better covered with foil instead of clear plastic during that early germination stage (remove, of course, as soon as any signs of seedlings appear!)
Use clean containers and clean germination mix
Germination mix is finer than regular soil mix, and gives better seed-to-soil contact. It is also light and well-drained which helps keep roots healthy.
Moisten the germination mix before adding seeds
Drainage is important, the germination mix should be moist, but not soppy wet! Drying out during germination is deadly, keep the mix moist continuously. A layer of clear plastic over the top of the container can help keep the moisture in, or you can mist the top of the soil several times a day. Some seeds will germinate in 3 days, others may take 3 weeks.
Pay attention to temperature
Many seeds germinate well with bottom heat, but once germinated most appreciate and grow better with fluctuating day and night temperatures, so turn off those heaters. Cool season flowers and vegetable will develop better if you can keep the seedlings from getting too warm. Try to keep them in that 50 to 60 degree range during the day, cooler at night.
Use a supplemental light source for best growth
Bright light from a window is great, but seedlings need really bright light to develop healthy, thick stems and proper growth. Consider hanging fluorescent or LED lights a few inches above the developing seedlings, and continue to raise the lights as the plants grow.
Maintain good airflow
Set up a fan to blow on your seedlings. This helps protect the delicate seedlings from damping off, a fungal disease that attacks the new stems at the soil level. The air movement also triggers production of structural proteins that thicken the cell walls and give the plants a stronger stem. Many commercial tomato and pepper seedling producers use brushing to toughen their plants. You can simulate this by gently running your hands over the tops of the seedlings each day.
By Patti Nagai, Emeritus Extension Professor
Master Gardeners volunteer at GreenWorks
March is not too early to plant! Extension Master Gardeners sowed pansy, geranium, aster, canna, and other flower seeds in our Green Works greenhouse in the past 3 weeks. Herbs and cool season vegetables are next, and it won’t be long before we start seeding warm season vegetables.
Cool season vegetables like cabbage, kohlrabi, spinach, and mustard can be started indoors if you have a cool space in which to grow them. An outdoor cold frame is useful for many cool season plants. Once the seedlings are growing they can be moved into the protected cold frame on days when the temperatures are above freezing. The cold frame is covered with a clear glass or plastic lid that lets light in, and the temperature at seedling level is ideally in the 40 to 55 degree range, perfect for those cool season crops.
Growing Vegetables at Home: Questions and Answers
Growing Vegetables in Containers
Using Crop Rotation in Home Vegetable Garden
Damping Off
