Magnolias are among the most interesting and best-known trees in the southern states.
About a dozen species and varieties are native to the South. Several others have been introduced, principally from Asia.
All varieties have relatively large flowers. The simple flower structure indicates they are among the most ancient trees. Possibly, as old as the ginkgo.
Fossil records show they were widely distributed before the Glacial Period. Today Magnolias have a rather limited restricted range.
Majestic Magnolia Grandiflora
When magnolias are mentioned, we usually think of the evergreen Magnolia grandiflora, the most beautiful and majestic.
Its bright green leaves, glossy on the upper surface and rusty brown beneath, are often 5” to 10” inches long and 2” to 3” inches wide—the largest leaves of any of our evergreen trees.
They vary in size on different trees found in the same locality and remain on the stout woolly brown stems for 2 years, being shed when the new leaf buds expand in the spring.
The solitary white flowers are borne at the tips of branches. Each flower has 3 sepals that are often petaloid in appearance, 6 to 15 petals, numerous stamens, and many pistils, which are more or less fused into an elongated axis that ripens into a leathery or cone-like fruit.
The seeds are generally red, and they are shed at maturity.
Although Magnolia grandiflora is usually in tree form, it is found along the dunes bordering the coastal highway on the Gulf Coast as a low, thick-growing shrub arising from an underground, trailing stem.
The leaves and flowers are somewhat smaller than those on the larger trees.
This peculiar growth habit enables us to espalier plants on walls where the leaves show off to advantage and where the flowers make a rather striking effect during spring and summer.
While this magnolia is generally regarded as a symbol of the South, large trees exist at least as far north as Cape May, New Jersey, and smaller ones survive much farther north.
In fact, some northern dealers state they can regularly withstand below-zero temperatures.
Different Magnolia Grandiflora Varieties
Several varieties of Magnolia grandiflora can be found in southern gardens.
The variety Gloriosa has the largest flowers, some measuring 14” inches in diameter, with broad brown leaves on the undersurface.
Ferruguinea, which blooms when quite young, has smaller flowers and leaves densely felted on the underside with brownish hairs.
Lanceolata has large flowers and oval or lanceolate leaves which are rusty brown underneath.
A type of the variety lanceolata has leaves that are pale green and hairless underneath, but it is disappointing for it seldom produces flowers.
The variety Undulata has broad leaves with wavy margins.
Goliath has large flowers and short, smooth, glossy, rounded leaves.
Question: How can I encourage a star magnolia to flower? It is 5 1/2′ feet tall with five or six stems growing from the trunk near the ground. It is in full sun and in winter the ground around it is mulched with oak leaves as well as marsh hay. BWT, Mich.
Answer: Consider omitting feeding for a year or two, since the tree may have had too much nitrogen. A couple of handfuls of superphosphate worked into the soil may also help.
Fragrant Magnolia Virginiana
Another interesting magnolia is Magnolia virginiana (Magnolia glauca), widely distributed throughout the coastal plain in wet woods as far north as Massachusetts.
Although its trunk sometimes reaches a diameter of 1’ foot and a height of 30’ to 40’ feet, it is usually a large shrub.
In fact, in pine woods, where the soil is acid and moist most of the year, it may be a small shrub flowering when 2’ or 3’ feet tall.
The leaves are semi-evergreen, 4” to 6” inches long, 1 ½” to 3’ inches wide, glossy green on the upper side, pale to nearly white, and hairy beneath.
During the first winter, they remain on the tree and are shed when new ones come out in April.
The flowers appear in late spring, are creamy white, measure 3” to 4” inches in diameter, and have a fragrance suggesting a gardenia.
Magnolia virginiana has been cultivated since Colonial days, but it seldom does as well in the garden as in the wild. In the North, it is a shrub.
Both Magnolia virginiana and Grandiflora are best transplanted in the spring after careful balling since their somewhat fleshy roots are easily injured.
As the lower branches of most of the magnolias grow near the ground, they can be layered and develop good roots in about 2 years.
Different Species Of Deciduous Magnolias
Four species of deciduous magnolias are fairly common in southern forests.
Magnolia Tripetala
The most widely distributed is Magnolia tripetala or the umbrella magnolia, also known as the cucumber tree.
The leaves are 10″ to 20″ inches long, 3 ½” to 9″ inches wide—broadest above the middle, bluntly pointed at the tip, and long pointed at the base.
They are arranged near the ends of branches, forming a sort of umbrella.
The flowers open in April are 8″ to 10″ inches in diameter. The narrow petals are at first widespread but soon become reflexed, showing the red cucumber-shaped fruit.
Like the other native magnolias, it is susceptible to fire and has been destroyed in many forests, although vigorous sprouts sometimes arise from the uninjured roots.
Magnolia tripetala is found in rich woodland soil near streams and may grow to 30′ to 40′ feet.
In Massachusetts’ Connecticut Valley, it has survived temperatures as low as 25° degrees Fahrenheit or more below zero.
Magnolia Acuminata
Magnolia acuminata is a similar deciduous species found on the moist, deep, fertile soils of the coves and lower slopes of mountains.
It is also known as a cucumber tree because of the shape of its fruit. The elliptic leaves are 6” to 10” inches long, 4” to 6” inches wide, sharp-pointed at the tip, rounded at the base, yellow-green and smooth above, whitish, hairy, or smooth beneath.
It blooms in April, and the flowers are about 10” inches wide. The greenish or pale yellow petals do not reflex appreciably when mature.
At first, a small greenish cone, the fruit is reddish-brown when mature and measures 1” to 3” inches in length.
As the scarlet seeds mature, they fall from the cone and remain suspended for a time on a slender white thread.
This is one of the hardiest of the species. Its natural range extends even up into southern Ontario.
Magnolia Fraseri
In the mountains of the southern states, you often find Magnolia fraseri, growing in moist soils, usually near a stream.
The leaves are 10” to 12” inches long, 6” to 7” wide, broadest toward the tip, and have 2 earlike lobes at the base.
They are bright green, smooth on both surfaces, and clustered at the end of the branches.
The tree rarely attains a height of more than 30’ feet, and branches near the ground frequently give it a shrubby appearance.
The flowers are 6” to 10” inches in diameter, the petals rather loosely arranged.
As the petals fall, the pinkish-green, cucumber-shaped fruit is revealed.
When mature, the fruit is 4” to 5” inches long, 1 ½” to 2” inches thick, and bears many scarlet seeds.
Magnolia cordata was first described by Michaux, and it resembles Magnolia acuminata very closely, but its flowers are smaller and yellow.
Magnolia Macrophylla
By far, the most striking and the rarest of the deciduous magnolias is Magnolia macrophylla or the great-leaved cucumber tree.
The leaves are the largest of any North American tree, except those of some palms, often measuring a foot in width and 30″ to 36″ inches in length.
They are rather thin, light green above, and whitish underneath.
The tip is bluntly pointed, and the base ends in two large auricles, somewhat resembling the leaves of Magnolia fraseri.
When they fall in the autumn, they make a white carpet.
The flowers are usually somewhat larger than those of Magnolia grandiflora, the petals strap-shaped with a purple spot near the base.
They are vase-shaped or constricted above the middle when they open in May.
The trees seem to be very sensitive to adverse conditions, and young shoots wither and die for no apparent reason.
They have been destroyed by fire in many forests. Occasionally, young trees spring up in ravines where the soil is deep and humus-filled.
They are difficult to transplant or layer but grow readily from seed gathered as soon as it is ripe and sown at once.
Many gardeners are trying to grow this interesting tree not only for its giant leaves and striking flowers but so those future botanists will not be forced to describe it as “another lost tree of Georgia.”
Asiatic Magnolia Species
Among the first harbingers of spring in the South are some of the magnolias introduced from Asia.
Magnolia Soulangeana
The most commonly seen is Magnolia soulangeana, a hybrid between Magnolia denudata and Magnolia liliflora. It comes into full flower around Atlanta about once every 3 years, for the last frost of spring often kills the flowers and young buds.
To avoid this, the original hybrid is being replaced by the variety nigra, which flowers about 2 weeks later.
Magnolia Stellata
Magnolia stellata, the star magnolia, a native of Japan, has attractive white flowers, and two pink varieties have been introduced, one called Halleana and the other Waterlily.
Like Magnolia soulangeana, their flowers are often killed by frosts which occur after the flowers have opened during warm winter spells.
The Asiatic species flower reliably well up into New England in the North, where flowering is conspicuously delayed.