How Tall Do Magnolia Trees Grow

If you’re planning your garden, one of the first questions you might ask is, how tall do magnolia trees grow? Reaching impressive heights is a hallmark of many magnolia species, but the final number can vary dramatically. Choosing the right one means understanding just how much sky it will claim.

From the towering Southern magnolia to the smaller star magnolia, their mature size impacts everything from planting location to long-term garden design. Let’s look at what you can expect from these beautiful trees.

The simple answer is: it depends entirely on the species and cultivar. Magnolias are a diverse group. Some stay shrub-sized, while others become forest giants. Knowing the potential of your chosen tree is the key to a happy, healthy garden for decades to come.

Factors That Influence Magnolia Tree Height

Several elements work together to determine your tree’s ultimate stature. It’s not just genetics.

Species and Cultivar: This is the biggest factor. A ‘Little Gem’ magnolia will never reach the heights of its parent, the Southern magnolia.
Climate and Hardiness Zone: Magnolias grow best in their preferred zones. A tree stressed by cold or excessive heat won’t reach its full potential height.
Sunlight: Most magnolias thrive in full sun to partial shade. More sun generally promotes stronger, taller growth.
Soil Conditions: Well-drained, slightly acidic, and nutrient-rich soil provides the ideal foundation for robust growth.
Water and Nutrients: Consistent moisture, especially in the early years, and proper fertilization support healthy development.

Height Profiles of Popular Magnolia Types

Here’s a breakdown of what you can expect from some of the most common magnolias.

Large Magnolia Trees (Over 30 feet tall)

These are the statement-makers, often used as majestic lawn specimens.

Southern Magnolia (Magnolia grandiflora): The classic evergreen. It typically grows 60 to 80 feet tall, and in ideal conditions, can soar past 100 feet. Its spread is often 30 to 50 feet.
Cucumber Tree (Magnolia acuminata): A large deciduous native that can reach 60 to 80 feet tall with a spread of 30 to 50 feet.
Bigleaf Magnolia (Magnolia macrophylla): Known for its enormous leaves, this tree grows 30 to 40 feet tall.

Medium-Sized Magnolia Trees (20 to 30 feet tall)

These offer significant presence without overwhelming a residential yard.

Saucer Magnolia (Magnolia x soulangeana): A beloved deciduous hybrid. It usually matures at 20 to 25 feet tall and wide, forming a large, multi-stemmed shrub or small tree.
Loebner Magnolia (Magnolia x loebneri): Such as the ‘Leonard Messel’ cultivar. These tend to reach 20 to 30 feet in height and spread.
Umbrella Magnolia (Magnolia tripetala): A native deciduous tree with a tropical look, growing 15 to 30 feet tall.

Small Magnolia Trees and Shrubs (Under 20 feet tall)

Perfect for compact spaces, patios, or as an accent plant.

Star Magnolia (Magnolia stellata): A slow-growing, deciduous shrub or small tree. It typically forms a rounded shape 15 to 20 feet tall and wide.
‘Little Gem’ Southern Magnolia: A dwarf cultivar of the giant. It’s evergreen and grows very slowly to about 15 to 20 feet tall, with a narrower spread of 7 to 10 feet.
‘Jane’ Magnolia (and other “girl” hybrids): Part of the Little Girl series, these are compact, deciduous shrubs reaching 10 to 15 feet tall and wide. They’re also known for late blooming, avoiding frost damage.

How to Manage and Support Your Magnolia’s Growth

You can’t change a tree’s genetic potential, but you can ensure it reaches it’s healthy best with proper care.

Planting for Success

Choose the Right Location: Give your tree enough space to reach its mature width. Check for overhead power lines and underground utilities. Remember, the roots can spread as wide as the canopy.
Plant Correctly: Dig a hole twice as wide as the root ball but no deeper. The top of the root ball should be level with or slightly above the soil surface. Backfill with native soil.
Water Deeply: Provide 1-2 inches of water per week for the first few years to establish a deep, strong root system.

Pruning and Maintenance

Magnolias generally require minimal pruning. The best time to prune is immediately after flowering for spring bloomers.

Only remove dead, damaged, or diseased wood.
To shape a young tree, remove select branches to encourage a strong structure.
Avoid heavy pruning, as magnolias don’t heal quickly and large cuts can invite disease.
Applying a layer of organic mulch around the base (but not touching the trunk) helps retain moisture and regulate soil temperature.

Common Challenges and Solutions

Even with great care, you might encounter issues. Here’s what to watch for.

Slow Growth or Stunting

If your magnolia seems to be growing slower than expected, consider these causes:

Poor Soil: Compacted, alkaline, or waterlogged soil will severely limit growth. A soil test can provide answers.
Insufficient Water: Young trees are especially vulnerable to drought stress.
Planting Too Deep: This is a common mistake that can suffocate roots and cause decline.

When a Tree Gets Too Large

Sometimes, a tree outgrows its space. For large magnolias, pruning is not a great long-term solution. It’s better to:

Consult a certified arborist for advice on selective thinning or reduction cuts, if absolutely necessary.
Consider that removal and replacement with a smaller cultivar might be the most sustainable option for a small garden.

Frequently Asked Questions (FAQ)

How fast do magnolia trees grow?

Growth rates vary. Southern magnolias grow at a medium pace, about 1-2 feet per year once established. Star and saucer magnolias are also moderate growers. Many of the smaller cultivars grow quite slowly.

What is the tallest magnolia tree ever recorded?

Record heights for Southern magnolias have been reported over 120 feet tall. These are exceptional specimens in perfect, wild growing conditions.

Can I keep a magnolia tree small by pruning?

You can manage size to a degree, but you cannot keep a giant Southern magnolia at 10 feet tall without harming its natural form and health. It’s always best to choose a cultivar that naturally fits your available space.

How wide do magnolia trees get?

The spread is often proportional to the height. Many magnolias, like the Southern, become as wide as they are tall. Smaller types like ‘Little Gem’ have a more columnar shape. Always check the expected width before planting near structures.

What magnolia tree stays the smallest?

Among the smallest are the ‘Jane’ and other Little Girl series magnolias, often topping out at 10-12 feet. Some dwarf Star magnolia cultivars also remain very compact, suitable for large containers.

Making Your Final Choice

Selecting a magnolia is a long-term commitment. Before you buy, research the mature height and spread of your preferred species or cultivar. Visit a local arboretum or nursery to see mature examples. Consider your soil, sunlight, and available space. With the right tree in the right place, you can enjoy its magnificent blooms and stately presence for generations, without worrying about it outgrowing its welcome. The key is matching the tree’s potential to your garden’s reality.