The Magnolia Tree
2011, Dorling Kindersley Limited
Magnolia grandiflora is a broadleaf evergreen tree that is noted for its attractive dark green leaves and its large, extremely fragrant flowers. It typically grows to 60 to 80 feet tall with a pyramidal to rounded crown.
If you had to name just one tree to symbolize the South, the classic magnolia tree, aka Magnolia grandiflora would be a fine choice.
Like the sassy female characters in the 1989 movie, Steel Magnolias, this Southeastern native with big, glossy leaves and fragrant flowers combines both beauty and strength.
What you'll need to know to grow these grand beauties:
- Magnolia grandiflora needs a lot of space. It’s an evergreen that thrives in zones 7 to 9, often reading 60 to 80 feet in height and 30 to 50 feet across.
- It prefers rich, well-drained soil, with a pH that ranges from neutral to slightly acidic. For best results, incorporate organic material into the soil when planting.
- Magnolias tolerate sun to partial shade, and open their sweetly scented blossoms in May and June.
- You can buy magnolias potted in containers or balled in burlap, but those planted in fall’s cooler temperatures develop strong roots faster than those planted when it’s hot and dry. Just be sure you don’t set your tree any deeper in the ground than it was already growing.
- Keep your young tree watered regularly and deeply, if rainfall is scarce. But don’t let it stand in water. Add mulch to help keep the roots cooler when the temperatures soar.
- Evergreen magnolias rarely need pruning, but if you cut yours back to control its size or remove a bad limb, prune before it puts out a flush of new spring growth. Deciduous magnolias are better pruned after their flowers fade. Cut any branches all the way down to the base, but be careful. Wounds may take some time to “scab” over, leaving the exposed wood susceptible to various diseases.
- Try planting your Magnolia grandiflora as a specimen tree, so it stands out against a wall, fence or other background that sets off its fuzzy buds and creamy-white blooms. But again, remember that most magnolias need plenty of room to grow, and they dislike being moved.
- While magnolias aren’t typically bothered by pests or disease, they can develop chlorosis, an iron deficiency. It’s characterized by leaves that turn yellow, although the veins remain green. Treat it by applying iron chelate, a product available from garden centers, and follow the directions on the label.
- Avoid walking or cultivating closely around magnolias, so you don’t compact the soil or disturb their roots.
- If your tree is growing in neutral to slightly acidic soil, and its growth is slow or weak, you can feed it with an acidic, slow-release fertilizer. Apply as directed on the product label, and if in doubt, underfeed to avoid burning the leaves. You can also top-dress established trees once a year with compost, peat moss or well-aged manure. Just be sure to work these amendments very, very lightly into the soil, to avoid harming the tree’s roots, and water them in thoroughly.
Types of magnolias to try in your garden:
- Sweet bay magnolia, M. virginiana - More cold tolerant than the grandiflora. Hardy to zone 5, it behaves as an evergreen in the Southeast, and as a semi-evergreen to deciduous tree in the North. It’s smaller than the grandiflora, too, growing only to about 30 feet in the North.
- Saucer magnolia, M. x soulangeana – The shape and color of their blossoms give these magnolias their nickname, tulip trees. Give them fertile, acidic soil that drains easily.
- Magnolias with star-shaped flowers –Deciduous trees in this group include Kobus magnolia (M. kobus), Loebner magnolia (M. x loebneri), and star magnolia (M. stellata). Like tulip trees, they may lose their first flowers to a late frost, but in general, they are cold hardy and heat tolerant.