How to Start Petunias


Petunias come in a variety of colors including pink, white, purple, red and yellow. Types of petunias include grandifloras, multiflora, milliflora and groundcover. Thriving in full sun, petunias are planted in flower pots, hanging baskets or directly in the ground. Growing petunias from seeds is an inexpensive way to begin a beautiful flower garden. Start seedlings indoors 10 to 12 weeks before the danger of the last frost has passed.


Step 1

Fill the seed tray or pre-used container with well-drained garden soil.

Step 2

Select pelted petunia seeds, if available, as they are easier to handle. Non-pelted seeds are extremely difficult to grasp. Spread the seeds over the top level of soil, leaving 4 to 5 inches in between each seed.

Step 3

Water the seedlings using a watering can or spray bottle. The soil should be moist but not soggy.

Step 4

Place the seedlings in a room between 70 and 85 degrees F. and out of direct sunlight.

Step 5

Move the seedlings to a sunny spot or a place under grow lights after they germinate, which is around five to 10 days.

Step 6

Fill a flower pot with well-drained garden soil, leaving about 3 inches from the top of the pot. Gently remove seedlings after they establish three leaves, then place in the flower pot. Fill in any extra spaces with additional soil. Spread an even layer of soil across the top of the pot.

Step 7

Place the pot outside in a spot with five to six hours of daily sunlight. Water when the soil's surface becomes dry, usually every four to five days in dry weather.

Tips and Warnings

  • Seedlings will die without regular watering.

Things You'll Need

  • Petunia seeds
  • Seed tray
  • Garden soil
  • Water


  • University of Minnesota Extension Service: Growing Petunias North Carolina State University Horticulture Information Leaflets:Time to Germinate
  • Iowa State Extension Service: Selecting and Planting Petunias
  • University of Minnesota Extension Service: Growing Petunias

Who Can Help

  • National Gardening Association
  • USDA Hardiness Plant Zone Map
  • Iowa State Extension: Growing Petunias
Keywords: petunias, starting petunias, petunia seeds

About this Author

Brandii Lacey began writing in 1997 at "The Mountain Times" in Boone, N.C. Her articles appear on, GardenGuides and eHow Home & Garden. She provides travel and lifestyle content for LIVESTRONG.COM. Lacey is the senior plays editor and on the nonfiction editorial team for "Mused Literary Review" magazine. She holds a Bachelor of Science in communications from Appalachian State University.