Geraniums are a group of flowering bedding plants that have withstood the test of time and remain one of the more popular flowering plants, according to North Carolina State University. Their popularity can be attributed to their vigor, choice of colors and growing habits. The geranium x 'Johnson's Blue' is also known by the name of Johnson's Blue Cranebill. This variety of geranium is both hardy and tolerant of a wide variety of soils, although it requires regular watering throughout its growing season. Growing Johnson's Blue geranium from seed will provide you with many of these prolific blooming plants for your flower garden.
Pour between 1 and 2 tablespoons of a liquid soap into a basin or sink that has been filled with hot water. Set each of the pots into the soapy solution. Use a brush to scrub each pot.
Measure out 1 cup bleach and pour it into a bucket or basin that contains 9 cups of plain water. Soak the pots in this solution for approximately 10 to 15 minutes to further sterilize the pots. This is necessary to help prevent any fungi from killing the seedlings.
Scoop a sterilized seed starting mix into the plastic pots until they are each filled to about 1/2 to 1 inch from the top. Pack the mixture firmly down into each of the pots to remove air pockets. You can use a metal spoon or a fork to accomplish this.
Nick or scratch off a section of the seed coat on each of the Geranium x 'Johnson's Blue' seeds. Use a nail file or a hobby knife to do this.
Plant 2 Geranium x 'Johnson's Blue' seeds into each of the plastic pots. Sprinkle a light layer, about 1/8 of an inch of the seed starting compost over the seeds. Mist each of the pots with a fine mist of water until the mixture becomes well moistened.
Cover the pots with a layer of plastic wrap. Transfer the pots to a location that will provide a lot of light, ideally between 8 and 10 hours a day. Avoid any location in direct sunlight which will create too much heat and scorch the seeds. A good temperature during the germination period is between 70 and 75 degrees Fahrenheit. Watch for the seeds to begin sprouting in about 7 to 10 days at the above conditions.
Remove the layer of plastic wrap from the pots once the seeds begin to sprout. Place the pots 4 to 6 inches away from a florescent light for about 8 to 10 hours a day to make sure the seedlings are provided enough light so they will not grow spindly.
Thin down the Geranium x 'Johnson's Blue' seedlings to one plant per pot once they have two pairs of leaves. To do this use a pair of scissors and snip off at the soil line the least hardy appearing seedling in each pot. Begin fertilizing the seedlings once they are about 2 to 3 weeks old. Use a liquid fertilizer and dilute it to half strength.
Transplant each of the Johnson's Blue geranium seedlings into a sun-filled to partially shaded location in your garden when they are about 3 to 4 inches tall. You can also plant them into tubs or barrels.