Fill a 3- to 4-inch growing container 3/4 full with a combination of equal parts peat moss and perlite. The selected container should have drainage holes in the bottom to prevent over-watering.
Add just enough water to moisten the growing mixture.
Sprinkle the dusty miller seeds across the surface of the mixture. Do not cover the seeds -- they will not germinate without sufficient light.
Stretch a clear plastic bag over the growing container and place a rubber band at the container's base to hold the bag in place.
Move the container to a location that receives indirect sunlight the majority of the day. Remove the plastic bag as soon as the seedlings start to emerge.
Water the young plants when the soil feels dry to the touch.
Transplant to a 6-inch growing container filled with potting soil when the plants are 4 inches tall. Move the dusty miller plants to the garden when they are 6 to 8 inches tall and all danger of frost has passed.