Learn which plants thrive in your Hardiness Zone with our new interactive map!

How to Plant Seeds in the Summer

By Barbara Fahs ; Updated September 21, 2017

Spring is not the only time you can start seeds. When you start certain plants in the summer months, they can give you a bounty of fall vegetables and even flowers for your Thanksgiving table. Cabbage, lettuce, potatoes, beets, broccoli, carrots and chard are only some of the veggies that will perform well for you when you start their seeds in July or August. Late summer is also a good time to plant a cover crop of fava beans or other plants that will give next summer’s garden added nutrients. Check seed catalogs to learn which varieties are best for summer seed starting and a fall harvest.

Fill your pots or flats with potting soil and then sprinkle them thoroughly with water.

Scatter seeds on top of the potting soil and then cover them with the recommended amount of soil. Follow directions on the seed packet for details. Sprinkle the soil again.

Place your pots or flats in an area that is not too hot during the middle of the day. Under a tree or an arbor is ideal because the seedlings will need some sunlight, but can get cooked by too much heat. Be sure to keep the soil surface moist by watering daily until the seeds have sprouted.

Transplant young plants to larger individual pots when they are 2 inches tall. Continue watering them and caring for them until they are 4 to 6 inches tall.

When your young plants are 4 to 6 inches tall and the weather has cooled off (usually in September if you started your seeds in July), transplant them into your garden. If a heat wave occurs (“Indian summer” can get hot even into October in some areas), provide young plants with shade by building a simple frame over which you drape shade cloth.


Things You Will Need

  • Nursery pots or flats
  • Potting soil
  • Seeds
  • Water
  • Area with filtered sunlight
  • Shade cloth (optional)


  • If your seedlings look “leggy,” move the pots or flats to an area that receives more light.
  • Some seeds do best if you sow them directly into the garden. It’s safe to plant onion seeds and radishes in the garden in July, for example: just be sure to keep them well watered until they are larger and the weather begins to cool a bit.
  • Plant garlic and shallot bulbs directly into the garden in September.


  • If you do a little research, you’ll learn that you must start seeds of tomatoes, cucumbers and other summer annuals in early spring because they need warm weather in order to grow and produce.

About the Author


Barbara Fahs lives on Hawaii island, where she has created Hi'iaka's Healing Herb Garden. Fahs wrote "Super Simple Guide to Creating Hawaiian Gardens" and has been a professional writer since 1984. She contributes to "Big Island Weekly," "Ke Ola" magazine and various websites. She earned her Bachelor of Arts at University of California, Santa Barbara and her Master of Arts from San Jose State University.