Pollinate alstroemeria in the morning before hot sun or wind can disperse the pollen. Alstroemeria flowers have both male and female parts in each flower. To create a cross between two different plants, select one that will provide the pollen and a second one that will receive it.
Select a alstroemeria flower that is fully open and identify the stamens. Each flower has five to six stamens that rise from the center of the flower. At the tip of the stamens is the anther. The anthers are covered in heavy, sticky pollen.
Brush a cotton swab over the pollen on the anthers lifting as much of it as possible. Take the pollen laden swab to a different flower for pollination.
Identify the stigma. The stigma rises out of the center of the flower and extends beyond the anthers. The stigma is sticky to attract pollen.
Brush the swab on the stigma to transfer the pollen. The seeds that flower produces will carry the genetic material of both alstroemeria plants.