The Blue Flag Iris is also known as the Iris versicolor or in the case of the Southern Blue Flag Iris, Iris virginica. They are wildflower perennials that are normally found in wet areas, such as marshes and bogs. They can be used as border plants in the wet areas of a pond or the more mature plants can be used in your water garden. Seed planting is a little more difficult than splitting the rhizomes and growing but can be done with some special care.
Place seeds just under the soil in the fall in climates that have frosts and freezes during the winter. You should place a cage or cover with cheesecloth so the birds or other wildlife does not eat the seeds. The location should be in a partially sunny, wet area.
For areas that do not have 3 months of freezing temperatures, place the seeds in a plastic bag with a little damp peat moss. Place in the refrigerator for a month and then in the freezer for 6 weeks. Go back to the refrigerator for at least 2 more weeks and they will be ready to plant.
Germination will naturally occur outdoors when it starts to get warm and sunny. Remove any cheesecloth that will restrict the growth of the seedlings. Keep the seedlings protected and damp.
Indoors, plant the seeds in peat pots and keep damp until spring. Place them in a partially sunny window to germinate.
Work some compost into the soil around the plants outdoors. Do not transplant for a water garden until they are well established. If planting for a water garden, do not submerge more than 6 inches when they are ready.
Plant the peat pots outdoors in a partially sunny, wet area. Dig a hole so the peat pot is level with the surrounding ground. If your area is not constantly wet, watering will be needed every day that is without rain.