Propagating Zinnias

In the Garden

• 1

  Place the seeds directly in garden soil once the soil has warmed above 70 degrees Fahrenheit. Press each seed into loosely cultivated soil until the seed is about one-eighth of an inch beneath the surface.

• 2

  Water the soil enough to keep it moist but not soggy for five to seven days, or until the seeds begin to sprout.

• 3

  Water the plants less often once they are 2 to 3 inches tall. Allow the soil to dry out until the top half inch of soil is dry before you water. Apply water to the soil around the plants, not the plants themselves, since wet leaves can lead to fungus growth that could kill the plants.

• 4

  Mulch around the plants when the plants are about 6 inches tall. Apply several inches of organic mulch around the plants.

• 5

  Fertilize the zinnias once a week with a fertilizer that contains 100 parts per million of Nitrogen. Work dry fertilizer into the soil around the plant, or water with a mixture of fertilizer and water.

In Flats

• 6

  Fill seedling flats with a seedling soil mixture four weeks before the last frost date.

• 7

  Plant one zinnia seed per cell of the flat. Press the seeds into the soil until the seed is about a half-inch below the soil surface.

• 8

  Keep the flats moist but not soggy to encourage germination. When the seedlings begin to emerge from the soil, water only when the soil dries out to a depth of half-inch.

• 9

  Keep the soil temperature between 75 and 78 degrees Fahrenheit for best germination. Setting the flats on a heat mat will help. Seeds should germinate in five to seven days.

• 10

  Set the flats in bright light. Zinnias enjoy full sun conditions.

• 11

  Fertilize the seedlings two times a week with a liquid fertilizer than contains 50 parts per million of nitrogen.

• 12

  Transplant seedlings into the garden or larger pots when they are 14 to 21 days old. Remove the entire cell from the seedling tray. Plant it so the stem of the zinnia is at the same depth in the ground as it was in the seedling tray.