Southern Magnolia Tree: When to Plant & Prune Full Grown (Tree Care)

Photo showing a number of Southern Magnolia trees with dense green leaves in oval frame on green background.

The Southern Magnolia (Magnolia Grandiflora) is an evergreen tree notable for its big fragrant white blooms and glossy dark green leaves that flourish on the high top of the tree.

It is a great way to attract birds to your yard in autumn, so it’s no wonder that many people want to plant this beautiful tree. Although it is not the largest species, a thick canopy and shallow root system make it one of the most common trees in the United States.

But, there are some things to know about how and when to plant a Southern Magnolia tree, and how to take care of it so that it will flourish.

Firstly, you’ll need a large area and the early care will involve mulching and lots of watering after you plant it in the right soil.

Here’s how to do it.

Southern Magnolia Tree Care

The Southern Magnolia tree is a beautiful display tree that is very simple to cultivate4 if you choose a location protected from severe winds with enough space for growth.

They are mostly cultivated in rows to act as a privacy screen or mark property limits. These trees are not suitable for a lawn because of their chaotic leaf shed in the spring and autumn. But, gardeners often use the sturdy leaf detritus as mulch if you plant it in an attractive garden bed.

Planting this tree in containers can be done at any time of the year, although the hottest months should be avoided, and those purchased balled and bur lapped should be planted between August and October.

The initial growth season may be marked by leaf drop due to transplant shock, which is common in this species.

Sunlight Requirements for Southern Magnolias

Although they thrive in full sun, Southern Magnolia trees like partial shade if the soil is not excessively moist; in wet, rich soil, these trees may grow well in full sun once they have established themselves. Your tree needs at least four hours of direct sunshine daily to yield good results. As an understory tree, the Southern Magnolia is tolerant of shade but requires full light to blossom effectively.

Soil Needs

It is preferable to grow Southern Magnolias on soils that are well-drained, loamy, acidic, and rich in nutrients. However, they can still perform well in different environments and pH levels.

Conditions that are too dry or wet for long will not foster the best growth.


Your Southern Magnolias will be able to handle dry conditions, provided it has enough space for root extension and the soil is not poor or dry. Once set, the tree may be watered once a week.

The soil drainage and rainfall your area receives will determine how often water is needed. Excess or too little water will make the leaves turn yellow.

Related Reading: Magnolia Tree Guide

It would be best if you mulch them, but always ensure the mulch does not come into contact with the tree’s trunk.

Humidity and Temperature Requirements

The tree species enjoy semi-tropical climates with moderate temperatures and humidity. Extreme temperatures should be avoided, and even a mild frost is enough to kill seedlings.


You should add fertilizer to your trees in the spring, summer, and autumn after they have started producing new growth.

Unless you reside in a region with infertile soil, your tree’s roots should spread enough to find enough nutrients for themselves by the fourth year.


Pruning the Southern Magnolia tree after the flowering season will give it a nice tree-like look and promote a tighter, compact form. It is important to have this done before winter since dormant Magnolia branches tend to mend more slowly.

Similarly, it is advisable to understand how to trim a Southern Magnolia tree to maintain a more open and natural shape and reduce the risk of illness and formation of suckers.

What Is the Growth Rate of a Southern Magnolia?

Below is a chart showing the growth rate of a Southern Magnolia.

Southern Magnolia tree growth chart showing full grown Southern Magnolia tree on a line graph with Southern Magnolia tree age on the x-axis and Southern Magnolia tree height on the y-axis.

The tree grows at a slow to medium rate. Depending on how fast the tree grows, the height can increase from 12 to 24 inches yearly.

Southern Magnolia

(Magnolia grandiflora)

Southern Magnolia tree in oval frame on green background.
  • Family: Magnoliaceae
  • Genus: Magnolia
  • Leaf: Dark green, alternate, grows up to 10 inches long
  • Bark: Smooth but as it matures, it forms scales; dark brown to gray
  • Blossoms: Saucer-shaped, white, emerges from May to June
  • Fruit: Cone-like and round, red
  • Native Habitat: Southeastern United States
  • Height: Up to 80 feet
  • Canopy: From 30 feet to 50 feet
  • Type: Evergreen
  • USDA Plant Hardiness Zone: 6a-10b

IUCN Red List of Threatened Species Ranking

Least Concern


Varieties of the Southern Magnolia Tree

As a result of the widespread cultivation of southern magnolias,1 there are several Southern magnolia varieties, some of which bloom early and others which have a more compact form or a thicker canopy.

Southern magnolia tree identification chart showing its leaves, flowers, tree, seeds and bark in oval frames.

The following are some well-known examples:

  • Edith Bougue (Magnolia grandiflora): Growing up to 30 feet tall, it is one of the most cold-hardy Southern Magnolia tree varieties. It has a pyramidal shape and becomes tighter with age.
  • Hasse (Magnolia grandiflora): With its compact, columnar structure, this cultivar functions well for usage in narrow areas or rows for screening. It generally grows up to 40 feet tall.
  • Little Gem (Magnolia grandiflora): If you are seeking a dwarf Southern Magnolia tree, this winner of several awards is a fantastic choice to consider. As one of the most modest varieties, it is often cultivated as a shrub and does not normally reach heights of more than 25 feet. Even if the leaves and flowers are on the smaller side, they still have a charming appearance, and the tree begins producing an abundance of flowers at a very early age.

Magnolia Propagation

It is possible to grow southern magnolia from cuttings; however, doing so might be difficult. If you are interested in giving this a go, here is some basic advice to keep in mind;

  • Summer is a good time to plant a southern magnolia tree. Choose a six-inch-long semi-hardwood cutting with at least a few leaves from young stock. Perform a clean incision just above the node. Take off any lower leaves.
  • Utilize a rooting hormone to increase your chances of success.
  • At a minimum of four inches in depth, place in a growing medium that is wet and well-drained.
  • When you transplant the cutting, you need to be careful not to injure the roots, which are both fleshy and sensitive.

Growing a Magnolia Grandiflora Plant From Seed

You may start your Southern Magnolia2 seedlings using these tips:

  • A tree with ripe cones may be used for this purpose. Achieve this by allowing the Southern Magnolia tree fruit to dry out completely. Extract the seed covering by soaking the seeds in warm water for a few days. Drain the water after the coating has softened.
  • Using a tissue, thoroughly dry the seeds. Two options for overwintering seeds are a cold frame or a plastic bag filled with damp peat, vermiculite, or sand and kept in the refrigerator for two months before planting. A seed might take up to 18 months to germinate.
  • Transplant the seedlings into a shady spot after they have grown big enough to handle. A cold box or greenhouse for their first whole winter is a good idea.
  • Put seedlings in the ground at least 6 inches tall, cover them with mulch, and keep them safe for the first couple of months.

Common Problems That Affect the Southern Magnolia Tree

People around the world, not only those from the southern United States, adore the majestic and old magnolia tree. Although magnolia trees are very hardy, a sick magnolia tree might harbor dangerous pathogens. Even if you never have to deal with the knowledge of magnolia illnesses,3 you should be informed of the most frequent ones.

Southern Magnolia Tree blossoms creamy white with delicate pink centers and buds forming on magnolia branches.

(Image: Katzenfee505)

How to cure a sick magnolia tree will always be based on its age and the severity of its symptoms. When dealing with more critical situations, you will need to use your best judgment due to the wide range of sizes and shapes of these trees. Magnolia owners should be aware of the following issues.

Algal Leaf Spot

To diagnose algal leaf spots on magnolia leaves, look for velvety reddish-brown spots with ciliated structures on the underparts. The good news is that this is not a bad condition, despite how bad it seems.

Related Reading: Sweet Bay Magnolia Tree Guide

You don’t need to cure this infection unless your tree is designed to be a showcase. Instead, water and nurture your tree to keep it healthy. Use a fungicide to get rid of it if you must, but be sure to get all the algal patches at once.


These infestations induce branch girdling, which might harm a huge tree. If a branch suddenly dies while the others are OK, it is time to seek how to trim the southern magnolia tree branch and check for other locations where the bark is ripping off, or strange knots are growing.

Southern Magnolia tree pruning of the canker and an inch or two of good tissue is the only method to avoid the infections.

Wood Rot

Wood rot may necessitate the use of tree surgery. It is possible to rescue your tree from wood rot if the illness is identified in its early stages, depending on the location of the rot. If you look closely, you will see indicators like wilting in portions of the tree’s canopy or patches of the bark that have begun to leak.

Related Reading: Magnolia Tree Care

The best course of action is to seek the advice of a professional arborist and buy a southern magnolia tree from a reputable vendor.

Fungal Leaf Spots

In addition to the fungal leaf spots, magnolias may suffer from a variety of other conditions that are more bark than bite. You can probably leave them alone if they are just on the surface or the same on both sides. Remove dead leaves or other plant residues located at the base of young Southern Magnolia to reduce the danger of developing these spots.

When choosing a sapling, purchase a Southern Magnolia from a local nursery. This will reduce the carbon footprint of the purchase and increase the carbon offset trees power, as if you had bought it form one of the best carbon offset providers.

To learn how much carbon your tree will sequester, use the calculator here:

A Southern Magnolia tree can provide numerous benefits to the ecosystem, as long as you take good care to help it flourish.

Frequently Asked Questions About Southern Magnolia Tree

Why Do Many of Magnolia's Smaller Branches Have Brown Leaves at the Tip?

An insect known as the black twig borer is to blame for this rot. Tiny spherical holes are bored into the base of the stem by the female beetle, which then incubates the egg. The twig is hollowed out by the larvae, which emerge and feed within. Although the tree is not in danger, the dead twig ends are a nuisance.

To eliminate the problem, gather and dispose of any fallen dead limbs. You may eliminate any that have not fallen by cutting three inches up from the perforations into living wood.

How Can I Protect the Fruits on My Southern Magnolia Tree?

The tree fruit draws squirrels, rabbits, and other birds to its branches. Make a cayenne pepper and water solution to spray on your tree if you want to keep animals away. Using this combination on other plants that squirrels seem to like might also be helpful. However, be careful if you have pets or young children around.

What Is the Southern Magnolia Growing Zone?

The Southern Magnolia tree zone ranges from 6 to 10. It prefers acidic to mildly alkaline soil that is well-drained and has full or partial sunlight. Similarly, the tree tolerates salt spray, making it a good choice for seaside gardening.

What Is the Difference Between a Little Gem and a Southern Magnolia?

The little is one of the most distinctive varieties. Its white flowers contrast beautifully with foliage green hues. The flowers are what differentiates the two trees. Flowers on Little Gem measure 8 inches in diameter, whereas those of Southern Magnolia measure 12 inches. When does a southern magnolia tree bloom the Southern Magnolia does not rebloom, while the little gem can rebloom anytime between late summer and early winter?

The size of the crown is the next distinguishing feature. In comparison, the Southern Magnolia may grow to a height of 80 feet and a diameter of 40 feet. Magnolias of the Little Gem kind grow to a height of 20-25 feet and a width of 10 feet. When deciding, remember that a Southern Magnolia will need much more space to thrive.

A Southern Magnolia requires a well-developed root system to maintain a huge crown. This signifies that this tree’s roots are widespread. Harm to foundations and other concrete buildings may occur if the Southern Magnolia is planted nearby. On the other hand, the roots of Little Gem Magnolia are smaller and less strong; thus, this does not occur.

My Tree Is Taking Many Years To Grow. Is There a Problem?

There is nothing wrong at all. It might take a long time for generic trees to get going when they are small. However, early bloomers such as the Little Gem and Teddy Bear begin flowering considerably earlier than other types. A mature Southern Magnolia tree for sale that has already bloomed or has flower buds on it is the only way to be certain.

When Does a Southern Magnolia Tree Bloom and Look Prettiest?

Southern Magnolia tree bloom time is in May and June, with more flowers produced throughout the summer.

How Big Does a Southern Magnolia Tree Get and How Long Does It Take?

After many years, Southern Magnolia tree size may reach a height and width of 60 to 80 feet in height and 40 feet in width, depending on the region in which they are planted. It’s good that home gardeners can plant more compact varieties that will not take over the whole yard.

Where Is the Best Place To Plant a Magnolia Tree and When Should You Plant a Southern Magnolia Tree?

Many people always ask where southern magnolia trees grow better. The species’ adaptability to many situations is a big part of its appeal. As long as you don’t plant them in an area with frequent heat waves or lengthy periods of drought, southern magnolias need little care.

Like most trees, spring planting after dangers of frost will work. Follow tree planting best practices to ensure that your sapling establishes a good root system.


1Clemson University. (2020, January 3). Magnolia. Clemson Cooperative Extension Home & Garden Information Center. Retrieved July 23, 2022, from <>

2Dotdash Meredith. (2021, December 14). How to Grow Magnolia Grandiflora (Southern Magnolia Trees). The Spruce. Retrieved July 23, 2022, from <>

3Dotdash Meredith. (2021, December 14). How to Grow Magnolia Grandiflora (Southern Magnolia Trees), Soil. The Spruce. Retrieved July 23, 2022, from <,high%20alkalinity%20aren%27t%20appreciated.>

4University of Florida. (2019, January 10). Southern Magnolia. UF/IFAS Gardening Solutions. Retrieved July 23, 2022, from <>

5Katzenfee50. Pixabay. Retrieved from, <>

6Species Information Image: Magnolia grandiflora full tree Photo by Medico1849. (2007, December 3) / Public domain. Cropped and added text, shape, and background elements. Wikimedia Commons. Retrieved January 17, 2024, from <>