How to Grow Geraniums From Seeds

Put potting soil in plastic flat six to eight weeks before the spring's last frost. Fill the flat with dirt to within 1/2 inch of the rim. Be sure the flat has adequate drainage for water by poking three or four holes in the bottom with a pen. Take pen and run it lightly the surface of the dirt from one end of the flat to another, creating three rows in which to plant your geranium seeds. Plant seeds approximately 1/2 inch apart, then cover with a thin layer of dirt. Spray mist from your spray bottle over the entire flat.

Insert the flat into a big plastic bag. Close the bag with a tie twist. Store the bag in a warm indoor area between 70 and 75 degrees Fahrenheit. Expect the germination process to last one to two weeks. After seven days have past, open the bag to check for sprouts. Take the flat out of the bag when sprouts emerge from the soil, which should stay moist.

Fill plastic six-hole containers with dirt. Gently take out sprouts from the flat once two leaves emerge on each seedling and place a seedling in each container hole. Move containers to a southern window for full-sun exposure and fertilize once a week with a water-soluble solution diluted to half strength.

After three or four days in the window, move seedling containers outdoors to a full-sun location. Increase outdoor exposure by one to two hours per day for a week, waiting to plant in your garden until the threat of frost has passed. Before planting seedlings, fertilize garden with a 10-10-10 mixture.

Place seedlings a foot apart in 4-inch-deep holes containing 2 inches of mulch in each hole. Cover roots with soil and water.