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Starting Plants Indoors

By Julie Richards ; Updated September 21, 2017

Get a jump on the summer garden by starting plants indoors. Tomato, pepper, and cucumber plants are easy to start and transplant well into the garden. The cost of starting your own garden plants indoors is much less expensive than buying flats of plants from the local nursery. Starting plants indoors also ensures you are growing the variety you want and does not limit you to the greenhouse garden center offerings.

Moisten the potting soil slightly with warm water but do not allow the soil to become saturated. Fill the growing tray with the potting soil. Make uniform holes for the seeds in the soil with your index finger.

Place 1 or 2 seeds in each hole of the soil and cover with a fine layer of soil. Cover the tray with the lid or clear plastic. Tape the plastic into place, if necessary. Label the growing tray to help remember what was planted.

Place pepper seed trays on a heat mat before setting in the light. Peppers like a warm temperature of 80 degrees for good germination. You can put other seed trays directly in a bright window or under the growing light.

Watch for the seeds to germinate and remove the plastic cover when 80% of the seeds have broke through. Mist the seedlings if the soil appears dry. Turn the growing trays daily to keep the light exposure even among the plants.

Adjust the light so the seedlings do not grow spindly and tall trying to reach the light source. Thin the seedlings if needed. Handle the thinned seedlings by the leaves to keep from damaging the tender stem, if you wan to transplant the thinned seedlings into another growing tray.

Allow the seedlings to grow for 3-4 weeks before hardening off the new plants. Harden off the plants by setting them outdoors in a shady location when daytime temperatures are above 50 degrees. Only set them out for an hour the first day. Lengthen the time spent outdoors each day until they are outside all day. Increase the sunlight exposure on a daily basis as well.

Transplant the new plants into the garden bed when all danger of frost has passed. Keep hot weather plants like tomatoes and peppers inside a couple extra weeks until night time temperatures remain above 60 degrees.


Things You Will Need

  • Growing trays
  • Grow tray lids (optional)
  • Clear plastic
  • Cellophane tape
  • Good-quality potting soil
  • Grow light
  • Plant labels
  • Heat mat (optional)

About the Author


Julie Richards is a freelance writer from Ohio. She has been writing poetry and short stories for over 30 years, and published a variety of e-books and articles on gardening, small business and farming. She is currently enrolled at Kent State University completing her bachelor's degree in English.