Evergreen Magnolia, Magnolia grandiflora - Care Instructions

The Content Of The Article:

Magnolia - Magnolia

The evergreen magnolia is one of the rarities in this country. It is rare to find the tree with the big white flowers. This magnolia is something very special, because it keeps its foliage even in winter. But many a gardener worries about the cold season, because the Magnolia grandiflora is known to be a sensitive to cool temperatures. For this reason, it is not recommended to plant a large-flowered magnolia in particularly cold areas in the field. Meanwhile, there are also a number of varieties, which are no longer so cold temperatures.

Short profile

  • botanical name: Magnolia grandiflora
  • other names: Great-blooded magnolia
  • belongs to the genus Magnolias
  • Growth height: up to about 25 meters
  • grows very slowly
  • Flowers: white, tulip-shaped, up to 20 cm in diameter
  • Flowering time: from May, scattered flowers until July
  • Foliage: dark green, leathery, shiny
  • evergreen


The evergreen magnolia is a very special species of the genus Magnolia (Magnolia), because it not only keeps its leaves all year round, it also forms very large flowers. Originally, the evergreen tree, which can reach over 25 m in height, grows from the southeast of North America. There you will find the tree mainly in coastal lowlands along the Gulf of Mexico in warm-temperate to subtropical climate with relatively high rainfall. The Magnolia grandiflora is considered a character plant of the southern states and is also affectionately called "Soutern Magnolia".


The Evergreen Magnolia prefers a sunny to half shady site, which offers protection, especially in the winter months. In wine-growing areas, it can be planted practically anywhere in the garden, insofar as the soil and lighting conditions are right. In a little cooler it feels better in a sheltered place.
  • Light conditions: sunny to light partial shade
  • Soil: humus with good water storage capacity, nutritious
  • pH: preferably in the slightly acidic range
  • protected from strong winds
  • because of the stature height best suited as a specimen plant.
Tip: For the undergrowth of the large-flowered magnolia, the dogwood (Cornus florida), the chamois (Euonymus americanus) and the virgin wax tree (Myrica cerifera) are particularly suitable.

frost hardiness

To sum up, the Evergreen Magnolia is very sensitive to frost, is simply wrong. The fact is, however, that there are big differences between species. Especially young magnolias are very sensitive to cold and icy winds. With age, when the tree or shrub has grown well, the winter hardiness is a little better, but is far from being comparable to the frost resistance of native woody plants. The following varieties should therefore only be planted in very warm areas, such as vineyards, in the field. Alternatively, of course, a tub planting is possible.
  • 'Little Gem': early flower bud, compact habit, frost-sensitive
  • 'Galissonière: comes from France and is considered the most common variety, not particularly frost hardy, but very heat tolerant
  • 'Goliath': easily upright growth up to 8 m, forms a closed, roundish crown, blooms already at a young age
Fortunately, there are also breeds that generally tolerate frost better than others. These varieties are usually from North America. These include:
  • 'Bracken's Brown Beauty': one of the frostiest species ever (down to -25 degrees), slightly smaller leaves and flowers, the crown is slightly pyramidal shaped
  • 'Edith Bogue': small growing species with light green underside, very hardy
  • 'Exmouth': very old variety (1737), slender crown, light foliage, tolerates persistent frosts
  • 'Victoria': compact, dense, slightly smaller growth, down to -25 degrees hardy, comes from Canada
Tip: Although some of the frost-susceptible magnolias survive in rough locations, after a few years the trees tend to develop a poorly-grown crown and produce only a few flowers.


Magnolia - Magnolia

The planting season for the large-flowered magnolia is ideally in spring. Since the tree can grow very large, it should be planted with a suitable distance to buildings and property boundaries. Larger plants (or already trees) can also be used in mild regions in autumn. In this case, a thick mulch layer should protect the plant from freezing the root ball.
  • Time: spring
  • Planting hole: at least double bale size
  • Enrich soil with humus
  • if necessary, incorporate grit or coarse sand (if there is a risk of waterlogging)

to water

Since the evergreen magnolia occurs in their native country, the southern United States, preferably on river valleys or in the vicinity of swamps, it also needs in the garden a soil that can store the moisture well. Persistent waterlogging does not tolerate the tree, but it tolerates short-term flooding. The soil should optimally be constantly moist. Therefore, in low-rainy phases, especially in midsummer a regular watering is necessary. Like other evergreen shrubs, the grandiflora evaporates water over its leaves in winter. Therefore, it must be sufficiently supplied with moisture even in the cold season. Dryness acknowledges the Magnolia grandiflora with leaf shedding.


This species of magnolia prefers heavy, nutrient-rich soils and must therefore be supplied with fertilizer if necessary. A lack of nutrients is clearly shown by the fact that the large-flowered magnolia suddenly loses more leaves, although it is sufficiently watered. Potted plants are supplied with a high-quality liquid fertilizer for potted plants via the irrigation water every two weeks during the growing season. In the case of planted specimens, it is recommended to apply compost three times, in March, May and June. Alternatively, a good organic-mineral combi fertilizer for flowering shrubs can be used.

Substrate for container plants

For the planting of the Magnolia grandiflora one thing is very important: very high quality soil. However, it is recommended that the evergreen magnolia is not permanently cultivated in the planter, because after 10 to 15 years at the latest, the tree (especially its roots) just too big for the bucket. The trees are replanted only every three to four years in spring, when the bale is well rooted.
  • coarse-grained constituents (such as expanded clay, lava granules, chippings)
  • provide structural stability and dissipate excess water well
  • moderate clay content
  • high humus content


Magnolias can be propagated by seeds, cuttings, droppings or even moss. The simplest method of propagation for inexperienced hobby gardeners is the cultivation of seeds or cuttings.


The timing of cutting cuttings differs from perennial magnolia species in evergreen magnolias. The cuttings are cut in late summer or early autumn by a healthy, vigorous shoot.
  • half lignified shoot tip
  • Length: about 10 to 15 cm
  • Remove lower blade pair
  • Scrape off the bark in the lower area
  • stuck in damp substrate
  • Substrate: earth-sand mixture, potting soil or cactus soil
  • frost-free and bright
  • Keep the soil slightly moist
  • Planting in the field (or tub) next spring


Magnolia - Magnolia

After flowering, the Large-flowered Magnolia makes inconspicuous, hairy seeds on which the reddish-brown seeds ripen. These can be taken for propagation. However, the cultivation of the seeds of magnolia is a bit expensive. First, the seeds must be freed from the orange seed coat, as this germ-inhibiting effect. For this purpose, the seeds can be rubbed several times, for example, with water and sharp sand. Before germination, a cold period is also necessary.
  • Put cleaned seeds in a bag with wet sand
  • store for several weeks in the vegetable compartment of the refrigerator
  • From about the fourth week, the seeds begin to germinate slowly
  • Gently remove seedlings and place in substrate
  • leave the remaining seeds in the bag and put it back in the fridge
  • Substrate: Cactus soil, potting soil or peat moss
  • Keep the soil slightly moist
  • Location: partial shade (not dark)
  • no direct sun
  • Temperature: 15-20 degrees
  • Growing pot: rather deep than wide
  • the seedling initially forms a taproot
  • later then a heart-shaped root system
Tip: The seedlings of the Large-flowered Magnolia have the ability to grow in the shade even under a nearly closed canopy. Therefore, they can easily be sown in the shade of the mother plant.

To cut

Anyone who brings an evergreen magnolia into the garden should plan plenty of space for the noble wood. Although the tree grows very slowly, in old age it can reach more than twenty meters in height. The crown is also quite expansive, with the branches of the wood usually branch only slightly. A Magnolia grandiflora does not necessarily have to be cut. It is sufficient to light them out regularly and to remove dead shoots. All large-flowered magnolias form their buds in the previous year and drive out of the old wood after the winter. If you do not want to give up flowering in the coming spring, you should take this into account when cutting.
  • Time: late winter
  • alternatively (without flower loss): after flowering
  • choose rain-free, slightly cloudy day for cutting
  • remove all dead and sick branches
  • to cut off intersecting or inwardly growing branches
  • should the crown grow denser, the branches are cut to about 2/3


Large-flowered magnolias cultivated in vineyards do not require special protection in winter. In all other regions, magnolia trees should be best protected from the freezing weather. If you plant your evergreen magnolia in the field, you should choose one of the frostier varieties to prevent frostbite failures. If such a specimen should freeze, it will be able to recover and expel from strong trunks and branches.

Outdoor plants

As a rule, it is sufficient to cover the sensitive root area of ​​Magnolia grandiflora with a thick layer of bark mulch, brushwood or foliage. This is necessary because the magnolia forms only very shallow roots that completely freeze at cold temperatures. Young trees can also be covered with a fleece or a jute sack if they are heavily illuminated by the sun in sub-zero temperatures. In this case, the plant evaporates water over the leaves, but can not absorb new water from the soil. So it comes to dehydration. As protection, the sack is simply slipped over the crown of the plant and tied down carefully. However, it must not remain longer than absolutely necessary to the plant.
Tip: The crown should never be covered with an air-impermeable film. So the air can not circulate the moisture accumulates. Most of the time mold is formed on the plant after a short time.

High trunks in the field

All plants, which are cultivated as Hochstamm, need in the field a special winter protection.
  • Wrap the stem with a fleece
  • Protect the crown with a jute sack in strong sunlight
  • Pile root area in layers
  • lower layer: bark mulch
  • middle layer: foliage
  • lower layer: straw or brushwood

potted plants

Magnolia - Magnolia

Evergreen magnolias in the tub should be brought over the cold season to a bright and cool, but frost-free quarters. Since the plants keep their foliage, it must not be too dark there. In principle, the warmer the location, the brighter. During this time you should not forget to pour the Magnolia grandiflora regularly (albeit more sparingly than in summer). Fertilization does not take place between August and March. Suitable for hibernation are:
  • frost-free greenhouses
  • cool conservatories
  • a garage with window
  • a cool, bright basement room

Diseases and pests

Basically, the evergreen magnolia is rarely haunted by pests or diseases. Nevertheless, it can come in an individual case to an infestation with pests or pathogens. The most common problems are with potted plants that are overwintered too warm, too dark or too dry:
  • mildew
  • White fly
  • Scale insects
Tip: As a rule, diseased magnolias recover quickly and only in the rarest cases do they suffer serious damage as a result of the infestation.
Evergreen magnolias are a very special asset to the garden. However, if you do not live in winter-mild areas (vineyards), you must always pay attention to the right variety when planting outdoors, because not all trees are frost-resistant. Delicate varieties should therefore be planted in a bucket and wintered in the Kalthaus. Those who want to be on the safe side in the outdoor planting, buy the best cold-resistant varieties: Magnolia grandiflora 'Bracken's Brown Beauty' or 'Victoria'.

Video Board: How to Garden Magnolia Trees : Garden Savvy.

© 2019 EN.Garden-Landscape.com. All Rights Reserved. When Copying Materials - The Reverse Link Is Required | Site Map