Magnolia trees are grown for their colorful, fragrant flowers and elegant form. But what fascinates horticulturalists and sets these trees apart from others is how they propagate. More than 80 species are native to the eastern United States and Southeast Asia, according to the United States National Arboretum. Hundreds of hybrids have been cultivated to enhance desirable physical attributes. All magnolia trees, however, use an ancient method of reproducing that doesn't involve the usual insects that other flowering trees, like crabapples, rely upon.
Magnolia trees have exhibited little adaptation over millions of years. Today's trees still rely on several beetle species to pollinate them rather than bees or other insects such as butterflies. Because of this, the U.S. National Arboretum characterizes them as "some of the most primitive of all flowering plants."
Fruit and Seeds
Magnolias sexually propagate via woody fruit that contains seeds. The green fruit resembles a small cone with scales, but because the seeds develop inside the fruit, these trees are classified as angiosperms rather than gymnosperms, as conifers are classified as. The scales keep the fruit compact, but as it matures, they split apart to reveal seeds that are covered in a red fleshy aril.
The fruit and seeds develop from beetle-pollinated flowers, many of which are legendary for their pleasing scent. The flowers do not produce nectar, but do contain lots of pollen that is high in protein. The beetles drawn to the flowers transfer the pollen as they eat it. Evolution has for the most part ensured that other animals, such as hummingbirds and bees, remain disinterested in magnolias.
Seed as Feed
Birds, particularly those that migrate long distances, feed upon the seeds. The aril around each seed is high in fat, which gives the birds a nutritional and energy boost before they begin to migrate in the fall.
Growing magnolia trees from seed is possible, but lengthy and not always easy. Collect the seeds as soon as possible from a tree when the fruit is mature, usually in late summer to early fall. Pick a whole fruit, allow it to dry for several days and then shake the seeds from the cone. Soak the seeds overnight in warm water and remove the fleshy coat by scraping against window screening. Sow the seeds immediately or cold stratify them by storing them for up to six months at 40 degrees Fahrenheit for spring planting. If planting in the spring, layer seeds and a moist peat mixture in a polyethylene bag and place the bag in the refrigerator set at 40 degrees F. Purchasing cuttings is more desirable because it can take magnolia trees up to 20 years to bloom if they are started from seeds.