While Asiatic lilies are most commonly grown from bulbs, but new lily plants can be propagated from seed. Growing lilies from seed is not for the novice gardener; the project requires patience and regular care. Four years after starting the seeds, you will have a viable Asiatic lily plant that bears flowers. Begin this project in summer when your lily plants are blooming.
Prune your lily plants after the first flowers begin to fade. Remove the dying flowers and cut off all but one to two pods per stem. You'll have fewer lily flowers, but the plant needs that energy to develop seed.
Wait for the seeds to develop, until early fall. Watch for the pods to turn yellow and feel soft. Do not wait for them to crack open.
Pick the pods when they are yellow. Bring the pods indoors and place them in a vase of water. Refresh the water each day. Wait for the pods to dry out to the touch, so you can harvest the seeds.
Crack open the dried pods and shake out the seeds onto a paper towel. Leave the seeds on the paper towel to air dry, in preparation for planting.
Inspect the seeds when they feel fully dry to the touch. Hold the seeds up to the light to check for embryos inside. If the seeds appear clear or white inside, discard them because they lack embryos.
Fill a seed starting tray with potting medium so you can plant your lily seed. Moisten the potting medium with water.
Place the lily seeds in the seed tray, leaving 1 inch of space between seeds. Rest them on the top of the potting medium.
Cover the seeds with 1/2 inch of potting medium.
Place the seed tray in a warm environment such as a greenhouse or interior shelf. The seeds should germinate within two weeks.