“Think of magnolias as you might fashion - there’s a size, shape, style, and color suited to the decor of just about any garden, even the smallest,” says Judie Evrard Brower of Tesselaar Plants, an international plant research company. “Some can even be container-grown.” And don’t think for a moment that they’re fragile. “Magnolias are easy to care for and disease-resistant,” Brower says. They’re also versatile; they can grow as a hedge or be trained to climb up a lattice against a wall.
Here in central Texas, caring for magnolias can take a small amount of effort. Although the species will grow here, even in rocky soils, their needs really should be assessed based on each individual site. Our soils vary widely. Some soils such as those of Dripping Springs and Wimberley are very rocky and riddled with shallow limestone and very little good soil (except near the river where the soil can be great!). The rocky soils are very high pH (alkaline) soils. Other areas such as downtown and East Austin, and Northwest Hills have much deeper soils. Areas by Lake Austin have flat alluvial and extremely fertile soils from years of silting and produce magnificent specimens. East of IH35 in Kyle and Buda the soils are a heavy black clay.
Having cared for magnolias in all these areas, I find that most of the problems magnolias have are soil related. Additionally, compaction and lack of mulch often exacerbate already poor soil conditions. Lack of water, in addition to one or more of these factors, is also a limiting factor in the summer months especially. Soil amendment helps, add finished compost as a top dressing around but not touching the trunk out several feet or better yet, out to the edge of the canopy, this will help with water retention and will lower the pH a bit. Also mulch to 3 inches (max) and keep your trees well watered during the hot summer months and you will find your magnolia is no longer thinning or stunted.
Magnolias are one of those species that, in addition to their macro-nutrient requirements (N,P,K,S,Ca,Mg), they also require certain micro-nutrients in larger amounts than other species. Iron and Zinc are two of the most widely lacking micro-nutrients for magnolias in this area. Zinc, for example, is needed for the blooms. Iron is needed to prevent interveinal chlorosis (yellowing between the leaf veins). Additionally, magnolias thrive in low pH, acidic soils. Although they will grow in alkaline rocky soils, they do not get large and grow very slowly, and are of course more prone to nutrient deficiencies, the compost really helps with this.
In addition to general soil amendment and mulching, yearly fertilization is also helpful. When I apply a general slow-release, organic, granular fertilizer I will sometimes add a magnolia ‘micro’ mix to add missing micro-nutrients. Though more and more I find that adding the compost really does the trick. I have brought many magnolias back in the central Texas area over several years, and find that they will thrive if given the right minerals, mulch, water and soil conditions, including lowering the Ph. If you have a stressed or stunted magnolia follow the guidelines above and its problems will be gone in no time at all.
So how about some of those other varieties I said existed? Some of my favorites are the complete opposite of the huge magnolia trees we envision when we close our eyes, they are dwarf magnolias and can grow well in our area and even in small spaces or containers.
Like Little Gem, "Teddy Bear" can grow up to twenty feet tall. Teddy Bear is a little larger, growing up to twelve feet wide and grows faster than Little Gem. The tree is evergreen and compact, with white flowers. Magnolias are a traditional part of many southern gardens, usually planted with camellia and other southern specialties. Plant Teddy Bear in full sun in well-drained soil. It is perfect for hardiness zones 7 to 9, so it is perfect for us.
That brings us to Ann, my mother’s favorite magnolia variety. Classified as a deciduous shrub rather than a tree, Magnolia "Ann" is hardy in zones 4 to 8 and only grows to ten feet tall. Depending upon your micro-climate, Ann may bloom from mid to late spring, or even into summer, producing a stunning array of purplish-red, chalice-shaped flowers. Ann may be used as a shrub or grown into a tree shape. Plant in acidic, moist soil in full sun and remember, Ann is a late bloomer.
Finally, one of the newest and prettiest of the Magnolia family, "Baby Grand" is pictured below. This wonderful specimen was discovered in Australia a few years back. It is an evergreen, has a rounded form, and is hardy in zones 7 to 9. Plant it in full sun and water it weekly and you will be rewarded with quite a show. Baby Grand produces large, fragrant white flowers in spring and summer. Use it as a specimen plant in the yard or plant anywhere very moist soil is a problem for other trees.
Chances are, once established any variety of magnolia will outlive any of us, and isn’t that a nice thing to pass on to the next generation!