Magnolia grandiflora (Flore Pleno) 'NANNETENSIS'® southern magnolia, bull bay
Magnolia
I consider the Southern magnolia (Magnolia grandiflora) the most beautiful flowering tree suitable for our climate. It is an evergreen woody plant (tree or shrub) native to the southeastern United States, naturally growing in the coastal plains and river bottoms of states from North Carolina to eastern Texas, often in moist, humus-rich soils and in a warm, humid climate. In its native habitat, wild specimens propadated by seeds can reach up to 30 meters, but cultivated varieties are much smaller and fit even into medium-sized gardens. It was brought to Europe in 1711 by the French naval officer and governor of New France, Roland Michel Barrin de La Galissonière, and in 1726 also to Great Britain by the English naturalist Mark Catesby. In America, it had been known long before its scientific description, which was first made by the Swedish naturalist Carl Linnaeus in 1759. Why so late? At that time, America was not yet “in full bloom” botanically and scientifically, so most new species were formally described only after their specimens reached European botanists.
The entire genus Magnolia belongs among the oldest flowering plants on Earth, with fossil finds over 90 million years old, documented from the Cretaceous period in North America, Europe, and Asia. Can you imagine dinosaurs stomping around them and pterosaurs flying above their canopies? Evolutionarily, magnolias developed even before bees appeared, and therefore their flowers are adapted to beetle pollination – they have firm, waxy petals and resilient reproductive organs that can withstand the rougher handling of these pollinators.
It is no wonder that the unique and beautiful Southern magnolia captivated European colonists in America. In the southeastern states of the USA, it soon became a common feature of gardens and city avenues, as well as a strong symbol of the “Old South.” Since the 19th century, it has been regarded as a sign of elegance, hospitality, and tradition, reflected in literature, art, and architecture. Its blossom has been the official state flower of Mississippi since 1952 and of Louisiana since 1900. While it appears on Mississippi’s state flag (since 2020), it is absent from Louisiana’s flag, which features a pelican feeding its young. In some towns, it was deliberately planted along main streets and near public buildings to strengthen Southern identity and local pride – a use of an ornamental tree as a political cultural symbol that is relatively rare among woody plants. In Europe, it naturally found its place to thrive throughout the Mediterranean basin and into the Middle East, and I must confess that it became the love of my life which is why I made it the flagship of our garden centre.
Nannetensis® is a French variety of bull bay magnolia that gained popularity at the turn of the millennium, probably thanks to internet that spread the information among plant enthusiasts, though it was first described already in 1865. It was formerly cultivated under various names combining words Flore Pleno (double flowers) and Nantes which is its city of origin. This beauty is a prolific bloomer, just like Goliath variety, making flowers from late spring until early autumn. They are large, about 24-26 cm across, creamy white, sweetly scented and open up one by one. Nannetensis magnolia is a stubborn lady as it often happens that one plant produces not only double flowers (with two sets of petals), but also fully double flowers with many dwarf petals inside the flower, as well as a few single flowers every now and then.
The leaves are evergreen, medium to dark green, tough and leathery, with undersides covered with rusty brown indumentum. It grows fast, making 30-40 cm per year. Pruning is not commonly recommended, still, if you have a small garden and need to keep this beauty smaller, shorten last year’s long shoots by a third or maximum a half if the tip of the branch does not have a flower bud (fat and short as opposed to a leaf bud that is slim and long). Do so after all frost in early spring. If the branch has a flower bud, cut it after the flower has faded. We strongly recommend regular fertilizing. To save time and worry here is a way to feed your magnolia only once a year: take a quality water-soluble fertilizer (e.g. Kristalon Gold) and use 10 times as much as advised in the instructions for 10 liters of water. Mix it well and slowly pour this shot in the arm onto the roots making sure the plant drinks it all and you will not let it drain off. It will darken the foliage colour in 7-10 days and make new leaves and shoots within maximum 3 weeks from application.
Find it a location with plenty of direct sunlight in summer for at least 6 hours a day, protected from cutting winds. It needs preferably acid soil, very rich in humus, moist but permeable. Evergreen magnolias like clay in lower part of the soil which is an excellent source of nutrients. However, if your soil is only clay, plant it about one third above the soil level and cover the sides with quality soil mixed with peat and substrate or compost. Never make a hill around the root ball, the sides must slant gradually since the most important roots are mainly horizontal. Do not stomp, walk or play on its roots. It does not take root disturbance. Keep it heavily mulched all year round. Nannetensis? magnolia proved hardy to -24°C (USDA zone 6) and has not been tested in lower zones yet. In winter provide extra watering in frost-free periods.
Last update 01-12-2013; 04-09-2025
