Plant two seeds into the center of each pot only 1/4-inch deep in spring as the days begin to lengthen. Lightly cover over the seeds with ½- to 1-inch deep of sphagnum peat moss without packing down the moss. Mist the moss on top to moisten it thoroughly.
Move the pot to a warm, sunny window. Place a clear, plastic bag upside down over the pot to retain moisture in the air around the soil. Leave the seed to germinate over a period of two to three weeks. Spray the soil with a light mist only when it appears dry.
Move the crepe myrtle seedling outdoors to a partially sunny area, preferably with afternoon shade. Continue to water and care for the plant in its container until you’re ready to transplant it either in early to midsummer or fall.