Morning Glory ~ Ipomoea
Image by: wintersown
Ipomoea varieties produce seeds in similar manner and this FAQ may be applied to all.
Morning glories are a lovely old-fashioned vining trumpet-shaped flower available in many colors and flower sizes, they are invaluable for covering an unsightly fence or creating seasonal screening as a living wall. Morning glories are excellent reseeders; so good at reseeding that if you plant them once you may never have to plant them again. To reduce their reseeding capability remove all vines after they are killed by frost, bag them, and set them out in the trash. Composting the plants cannot assure that all seeds will be killed.
Morning glories produce clusters of round seed pods suspended from their vines. When they are mature the pods turn papery brown and are brittle. The mature seeds are dark-brown to matte-black, wedge shaped, and sized between and 1/8" and 1/4" long; a few, such as Hawaiian Wood Rose, are slightly larger.
Seed collection is easy. To collect the seeds simply clasp the papery-brown pods with one hand and crumble the seeds into a cup held below with your other hand. Immature seeds will not come free. Dry the seeds for about a week on an open plate before packing, allow for more drying time if the seeds are large and/or the weather is damp.