Grow Geraniums From Seed

If you love geraniums' bright colors and long-lasting blooms but want something a little more unusual than the varieties sold at garden centers, why not start your own geraniums from seed?

Geraniums grow slowly, so start from seed now for spring blooms. Mature plants will flower about 12 to 16 weeks after you sow seed.

To start geraniums from seed:

  • Plant seeds 2 to 3 inches apart and 1/8 inch deep in a seed-starting mix.
  • Cover the container with clear plastic and place in bright indirect light at about 75ºF. Keep soil moist but not soggy.

  • When the first set of true leaves appears, transplant seedlings into individual containers filled with potting mix.
  • Geranium seedlings do best with 12 to 16 hours of light a day. Fluorescent lights placed 4 to 6 inches above the plants work well.
  • Water only when the soil is dry. Fertilize every week with a houseplant fertilizer at one-fourth its recommended strength.
  • Harden off the plants by placing them outdoors for progressively longer periods of time. This could take seven to ten days.
  • Plant geraniums outdoors when danger of frost has passed.