The American Gardener
 
 


Web Special
Propagating Native Magnolias
By Gil Nelson

Commercially, magnolias have been propagated by grafting a cutting (scion) from a favorite plant onto the rootstock of another plant, often a seedling of a different species. Grafting is most often used for creating genetically identical cultivars. Genetic clones may also be reproduced from rooted cuttings. This process involves severing several inches of new growth from a favorite plant in early summer, wounding and dipping the bottom of the stem into a rooting hormone, then sticking the cutting into a rooting medium. Best results are achieved with the use of a misting system and greenhouse. Many home-based magnolia enthusiasts lack the time and facilities for grafting or rooting, so they grow native magnolias from seeds.

Nurseryman Dan Miller, owner of Trillium Gardens, a wholesale nursery in Tallahassee, Florida, has been propagating and growing native deciduous magnolias from seed for many years. Miller collects seeds in late summer, just as they become visible on the cone. Because wildlife enjoy the seeds, collect cones before they fall to obtain a larger crop of seeds.

The seed coats of many plant species, including the magnolias, contain chemical germination inhibitors designed to prevent untimely natural germination. Because of this, Miller soaks the seeds in water for up to three days, until they become soft and begin to putrefy, then gently scrapes them between squares of screen to loosen the outer coating. Once the coats are removed, Miller washes the seeds thoroughly, an admittedly time consuming process. And since many magnolia species also require a period of cold treatment to break embryo dormancy, Miller dries the seeds on paper towels, deposits them in a sealable plastic bag, and stores them in a standard refrigerator for about three to four months.

Since Miller's nursery is located in USDA Hardiness Zone 9, he sows his seeds in early December, in anticipation of a late February germination. He keeps the germination containers in the greenhouse until the chance of frost has passed, then pots and moves the plants outside. Those in colder regions or those without a greenhouse should sow the seeds after the threat of frost has passed.