How to Propagate Geraniums From Commercial Seed

Sowing Annual Geraniums

• 1

  Sow annual geranium seeds in late winter four months before you want them to bloom. Fill a 6-inch clay azalea pot to within 5/8 inch of its rim with damp seed-starting mix. (Use equal parts of peat and horticultural vermiculite if you don't have seed-starting mix.)

• 2

  Plant the seeds 2 inches apart. Cover them with 1/8 inch of granite chicken grit or sand.

• 3

  Place the pot in a flat that contains an inch or so of water until the mix and grit are damp. Remove the pot from the flat and cover it with plastic wrap to retain the moisture.

• 4

  Place the pot under the center of grow-lights at a temperature of about 75 degrees Fahrenheit. Watch for the seeds to germinate in as little as five days to as long as four weeks.

• 5

  Remove the plastic wrap and keep the seedlings under the grow-lights, with their tips about 4 inches beneath the fluorescent tubes. Time the lights to run for 16 hours per day.

• 6

  Transplant the seedlings, once they each have four leaves, into individual clay seedling pots filled with cactus potting soil. Test the surface of the soil with a fingertip and water the soil when it no longer clings. Add some liquid houseplant fertilizer to the water at a quarter strength -- about five drops per quart of water -- once a week.

Sowing Hardy Geraniums

• 7

  Purchase hardy geranium seeds in early spring. After tamping seed-starting mix into a 6-inch clay azalea pot, sow the seeds 1 inch apart on the surface. Barely cover them with the mix and add 1/4 inch of granite chicken grit or sand.

• 8

  Bury the pot up to its rim in damp soil inside an outdoor cold frame in the shade. Check the pot occasionally to make sure the mix is staying damp. Expect the seeds to germinate in one to three months.

• 9

  Transplant the seedlings into individual seedling pots of potting soil once they are large enough to separate. Grow them on in the cold frame until late spring, fertilizing them every two weeks with 3 tablespoons of a liquid kelp fertilizer per gallon of water.

• 10

  Gradually expose the seedlings to the open air and additional sunlight for two weeks before transplanting them into the garden, choosing sites in full sun or partial shade.