New Guinea Impatiens have only been available since their discovery in the mountains of New Guinea in the late 1970s. Many varieties of New Guinea Impatiens do not produce seeds and can only be propagated through cuttings. However, more and more varieties of New Guinea Impatiens are being bred to produce seeds, among them the Firelake and the Java Flame varieties.
Choose a variety of New Guinea Impatiens that produces seeds--not all varieties do. Talk to other gardeners or to your local nursery to determine which varieties produce seeds.
Wait for the plants to flower. Allow the flowers to remain on the plants. Once the flowers begin to lose their petals place a baggie over the entire flower and tie a string around the mouth of the baggie so any seeds forming inside the baggie cannot escape.
Watch for the development of a seeds pod. Seed pods develop from the center of the flower as the petals fall away. Allow the pod to grow and mature within the collection baggie.
Remove the baggie along with the seed pod once the pod has become dry and brown. Do not remove the pod from the baggie.
Crush the seeds pod gently between your thumb and forefinger, rolling the pod gently until it breaks open, spilling its small, black seeds. Carefully lay the contents of the crushed seed pod out on a paper towel and pick out the seeds. Place them in another baggie and store them in a cool, dry location until you are ready to plant them.