Why Invasive Mimosa Trees Are One Of The Top Silk Trees For Sale

A close-up shot of pink Mimosa Tree flowers, with 8 Billion Trees watermark.

You may not have heard of mimosa trees, but chances are if you’ve ever been in the southeast United States, you’ve seen one.

These pretty pink trees are actually a silk tree, a type of tree native to Asia, but very popular as an ornamental tree for landscaping in the US.

However, this glamorous tree may not be as good an option for your backyard as you might think.

Keep reading to find out why…

What Is Albizia julibrissin, or the Mimosa Tree?

Many people think that mimosa — scientific name A. julibrissin, and otherwise known as Persian silk trees or pink silk trees — are one of the prettiest trees in the world… and they aren’t wrong. With leaves shaped like delicate ferns and sweet-smelling pink puffballs for flowers, its beauty is unique and rare to find in most native trees. It also blooms during the summer, unlike most other trees, giving it a distinct advantage in the beauty department for year-round gardens.1

The flowers are attractive not only to homeowners, but also butterflies and hummingbirds, which is an exciting prospect to most gardeners. They range in color from nearly red to white, with most being flesh-pink or bright pink. The variety of colors is due to genetic variation, but pink is the dominant color gene, so it is what you’d see most often. In most states, the tree blooms starting in June and into July.1

Mimosa Tree identification chart showing Mimosa tree leaves, Mimosa Tree flowers, Mimosa tree fruit, and Mimosa tree bark in a circle frames on a green background.

These flowering trees also produce numerous seed pods, which contain 5-10 seeds each. In these seeds is a neurotoxin, which can be toxic to dogs and livestock so use caution around these trees if you have these animals. They will stay dormant for extended periods of time, and are easily distributed by water and wind. Because of this, seeds of mimosa trees located near rivers can travel surprisingly long distances before germinating.5

Although they have a tropical look, these trees are also very hardy and adaptable, meaning they’ll survive in nearly any soil type. They’re also drought tolerant and can handle either full sun or partial shade. All of this amounts to the nearly perfect landscaping tree.2

As an ornamental species, it is also used often as a roadside tree due to its ability to withstand air pollution, and its large root system helps prevent soil erosion. In other instances, this tree can be cultivated into a beautiful, though rather problematic and short-lived, bonsai tree. In some agroforestry systems in the southeastern US, it’s also grown in rows that are periodically pruned to use for mulch and improved soil.9

What About A Summer Chocolate Mimosa Tree?

A new kind of mimosa tree has entered the market that expands the color variety beyond the flower, to the leaves. The ‘Summer Chocolate’ variety features a purple-bronze colored leaf, which looks particularly interesting in combination with the pink flowers.1

It’s received a lot of hype in the gardening world, and many people are now enjoying this new variety in their own gardens and yards. Beyond the leaf color, there are not any other differences between the Summer Chocolate Mimosa Tree and the normal variety of this silk tree. It still blooms during summer, and produces thousands of seeds.1

Where Are Mimosa Trees Found?

Native to the Middle East and Asia, mimosa was originally brought to the US by a famous French botanist, Andre Michaux, who used it in his botanical garden in South Carolina. It turned out to love the southern climate, and from there became a popular decorative tree for colonial homes all across the south.1

Although it was introduced as an ornamental tree, it eventually escaped cultivation and can now be found growing alongside roadsides, in forests, along streams, and in clearings all over the southeastern US, competing with native species for water, nutrients, and light.5

An image of mimosa tree saplings in a nursery in Brazil, with 8 Billion Trees watermark.

Its sweet smelling flowers are also widely cultivated in England, the Southern US, the Mediterranean, and Argentina. In Italy, it’s cultivated in nearly every region and even grows wild in some towns.9

Available for around $100 depending on the size, you can find mimosa trees for sale at many popular landscaping vendors and on their websites, like The Tree Center of Fast Growing Trees.2,6 There are also seed packets available on various online sources, and the abundant seed pods can be gathered from any pre-existing tree to germinate and grow.2

Many online stores or local landscaping companies will try to make them a big seller by marking them as fast growers, among other enticing mimosa tree facts like its rapid growth and ability to attract hummingbirds. The prices and sizes available differ, but one thing stays the same: they advertise the combination of a mimosa’s good looks with their hardy demeanor.2

Are These Beautiful Mimosa Trees Actually Invasive?

These trees are highly desired for their appearance, but are considered invasive by authorities.

Because the tree is originally from areas around China, it’s non-native roots turn invasive when grown in the US. The tree’s population has become out of control, rampaging across the southeast region of the country, among other areas. It’s here that they compete with local vegetation, and end up choking out other native plants by stealing their sunlight and nutrients.3

Mimosa is considered a non-native invasive weed and not recommended for any use, including landscaping, by the following bodies:3,4

  • Southeast Exotic Pest Plant Council
  • IFAS Assessment
  • Georgia Exotic Pest Plant Council
  • Florida Exotic Pest Plant Council
  • The U.S Forest Service, APHIS and UGA
  • The National Park Service

This plant is mainly only considered a weed in the US, where it is being monitored in 13 states in guidance with the United States Forest Service (USFS) policy. It’s considered a category A (severe threat) weed in Tennessee, where it grows along many roads, disrupted areas, and stream banks. It’s also considered one of the top ten invasive species in Georgia, and is a category 1 (altering the plant community) invasive species in Florida. The species is now officially listed as moderately invasive (minor influence on ecosystem and local plant life) in Virginia, as well.9

With only one natural enemy to keep it in check — Fusarium fungus wilt — mimosa has very little holding it back from spreading its seeds across the entire country. In the words of one horticulture expert, this tree “laughs at heat and drought, and does not mind if you spray-paint the trunk white, hang tires from the branches, or park your pickup on top of its roots.”1

In horticulture, mimosa trees are considered a ‘pioneer species,’ because if all native vegetation is removed and the tree canopy opened to let in light, this is one of the first trees to appear. That’s why it grows along just about every road in the south, and continues spreading. It doesn’t grow in northern states as much because the climate is too cold for them there, but that might change too, with global warming growing into a stronger threat every day.1

Why Knowing Invasive Species Matters

Mimosa Trees are not the only invasive species that have been introduced to the United States for landscaping purposes, only to wind up taking over the landscape itself. Kudzu, English ivy, Japanese honeysuckle, bamboo, privet, and Chinese wisteria are all aggressively invasive species taking over the country from the south up, killing any other plants in their path… alongside mimosa trees.4

An invasive species is an aggressive, non-native plant that has been introduced into an ecosystem where it gains a distinct advantage over the pre-existing native plants. This causes the invasive plant to out-compete, literally choking out the other plants in the way. It works the same way with invasive animals. When the new species is introduced, the carefully balanced ecosystem is thrown off, and native animals suffer.5

Invasive species of any kind can wreak havoc and cause irreparable environmental damage by displacing desirable native species, whether plant or animal.

A famous example of this is the introduction of the cane toad in Australia.

Cane toads became invasive in Australia after being introduced to control beetles that were destroying sugarcane crops. These toads are poisonous to predators that try to eat them, so had no natural enemies in Australia. This allowed them to spread across the continent at astounding rates. Since their introduction, the range of these toads has spread westward at approximately 25-37 miles each year. The cane toad’s population grew exponentially, with this animal filling fields, covering roads, getting into houses, and competing with native species.8

For example, one study found that these pests have ruined one-third of the nests of ground-nesting rainbow bee-eaters, an Australian bird, by invading their burrows and eating their eggs and young.8

The cane toad might be one of the most notable examples of the detrimental effects of introducing an invasive species, but there are hundreds all over the world, and this pink silk tree is following in their footsteps… fast.

Although mimosa is a plant, their invasive nature can affect animals as well. Various songbirds are dependent on the caterpillars and other insects that are found on native plants, to feed their young. These food sources are increasingly scarce, due to invasive species like the mimosa tree.5

Now, it should be stressed that these plants are only invasive because they were introduced to a new habitat. In their native ecosystems, mimosa trees do not pose a threat because they occupy a special place in the balance of vegetation in the area. In the wild, silk trees across Iran, China, and Korea live in dry plains and sandy valleys, and don’t escape those regions to invade others, remaining perfectly safe.7

Close up image of pink mimosa tree bark and branches with pink mimosa flowers clustered.

(Image: leoleobobeo10)

In fact, as native plants, they have more uses than just being decorative. In Central America, an insect called a thornbug prefer mimosa branches for mating and overwintering, making the tree a crucial part of their life cycle. Silk tree wood can also be used to make furniture, and the leaves of the mimosa can be used to treat the rash of a stinging nettle, providing almost instantaneous relief.9

What’s more, these leaves can be cooked and used as herbs or dried and used as tea, while the cooked flowers can be eaten as well. In China, the flowers are used as medicine for digestive issues, insomnia, irritability, and used as a sedative. The bark can also be used as a sedative, or diuretic, and is used to treat insomnia, boils, and external injuries or swelling.

Even beyond the bark and leaves, a gummy extract made from the plant is used as a plaster for abscesses and in treatment of fractures and sprains. All of these useful qualities reign supreme in the mimosa’s native lands, while the same tree in the US becomes an invasive, yet decorative, plant.9

Do You Still Want to Plant Mimosa Trees in Landscaping? Try This Instead

Even if their invasive nature is not enough to dissuade people from using it’s pretty pink flowers for landscaping purposes, there are other reasons that may cause them to think twice before adding it to their garden.

Like most fast-growing trees, mimosa is notorious for having a short lifespan. It’s also subject to many pests and diseases, and will die very easily, and quickly.1 Some of the pests that might fester a mimosa are the mimosa webworm, which make big, ghostly nests in the trees, as well as mites and cottony cushion scale.

Mimosa tree growth chart showing a line graph with Mimosa tree age on the x-axis and Mimosa tree height on the y-axis.

Some people try to manage infestations by encouraging beneficial insects, but most prefer the use of insecticides and miticides. Unfortunately, the excess amount of insecticides and other harmful chemicals to keep these trees alive end up in run-off water, feeding into our rivers and streams and harming wildlife.6

What’s more, when the flowers fade and drop off, the hundreds of 6-inch seed pods begin to hang from every branch. For a lot of people, these seed pods are considered unsightly.. Especially because they persist all throughout winter, when the leaves fall, leaving just big brown bean-shaped pods hanging from its branches.

Each of those pods eventually drop, leading to extensive and annoying pick-up, especially if the tree is located over pavement or a driveway that holds cars. All of those seeds then start to germinate everywhere they end up, in cracks of the sidewalk, along fences, and in neighbor’s yards.1

Another drawback to using these trees in landscaping is mimosa wilt. This disease is becoming more and more of an issue across the country and kills many roadside trees. Infected trees’ leaves begin to pale and droop, then turn yellow and fall off the tree. Eventually, because the tree cannot keep any leaves with which to photosynthesize, the tree dies. This usually happens within a year. While this disease may help control the population of mimosas, they are still not recommended for planting in non-native areas.3

What Should You Plant Instead?

If you love the look of these silk trees but don’t want to contribute to their spread, try planting one of these similar trees:

  • Sweet Acacia: This plant somewhat resembles invasive mimosas, featuring dainty foliage and yellow puffy flowers.3
  • Red Bottlebrush or Dwarf Powderpuff: These two plants will produce delicate flowers that look like those of the mimosa tree.3
  • Sourwood: This species produces blooms during the summer like a mimosa, and the flowers attract helpful honeybees.5
  • Buttonbush: Another plant that has puffball flowers that bloom in June, this large tree-like shrub attracts bumblebees and butterflies.5

If these alternatives don’t tickle your fancy, there are plenty of other options for landscaping with trees. No matter where you live, or what style of garden you may prefer, trees can provide a valuable aspect to your landscaping.

According to landscapers, one of the first questions to ask when decorating an area is “Where do I have trees already?” followed by “What trees would I want to add, and where?”

As your garden’s biggest element, the placement of trees can have a big effect on what other plants you’ll want to incorporate, and where… both for practical and aesthetic reasons. They offer shade and shelter from the wind, which can provide a more varied landscape for shade-loving plants, as well as enhance your comfort and considerably reduce your household energy consumption from cooling.

On the other hand, trees can become design elements by establishing scale, framing the house, providing color with their blooms and foliage, or drawing the eye to attractive elements that you want to highlight.

One of the most important contributions a tree can make to a backyard is longevity. While a bush or flower may last a year, or even five, an oak can live for hundreds. A dignified tree as the centerpiece of your garden can become a legacy that will span over generations of those who will live in that home.

When selecting a tree for your yard, pick one based on the benefits it may provide. Picking a tall species with a large canopy will help shade a yard, while choosing evergreen trees with foliage that reaches the ground might act as a fence of sorts, to create privacy. For adding a focal point to your yard, research native trees that have striking formations, flowers, foliage, or bark.1

Other factors to consider include:1

  • Do you want a deciduous or evergreen tree? Deciduous trees drop their leaves in the fall, so you may have to rake them up in the fall.
  • Consider the growth rate of the tree, and the ultimate size once it’s fully grown. If you want shade or privacy quickly, choose a fast-growing species.
  • If you choose a larger tree, plan ahead and make sure you don’t plant it anywhere where the roots can crack sidewalks, mess up water lines, or run into the foundations of your house.

By avoiding invasive species, people have the ability to bring naturally occurring plants in the southeast back into the ecosystem, to restore their rightful balance. Pretty much any invasive species has a native alternative that achieves the same desired results.5 Choose wisely, and enjoy the natural beauty of your region.

Keeping Mimosa Trees A Healthy Part of Earth’s Ecosystems

If you’ve already got mimosa trees growing up in your backyard, fret not. The best way to get rid of a mimosa is to cut it down as close to the ground as possible. If you only have small saplings, or the tree re-sprouts, they can be pulled up by hand… but make sure you get all of the roots. It may take a few cycles of chopping, re-sprouting, and pulling, but eventually the tree will stop coming back.3

Close up angle shot of a Mimosa tree and its branches, green leaves and pink flowers.

(Image: AnRo000211)

The best thing you can do otherwise is to learn how to recognize this tree, and take action to reduce and mitigate its spread.3 To achieve good environmental stewardship and conserve our natural history, people must remove these plants from their landscapes and allow them to exist where they do no harm, in their native habitats.


References

1Bender, S. (n.d.). “Mimosa – The Wonderful, Awful Weed.” Southern Living. Retrieved September 1, 2021, from https://www.southernliving.com/garden/grumpy-gardener/mimosa-the-wonderful-weed. 

2Craig, W. (n.d).“Mimosa Tree.” FastGrowingTrees.Com, Retrieved September 1, 2021, from https://www.fast-growing-trees.com/products/mimosa.

3Mimosa Tree | Invasive (No Uses). (n.d.). University of Florida Institute of Food and Agricultural Sciences (IFAS). Gardening Solutions. Retrieved September 1, 2021, from https://gardeningsolutions.ifas.ufl.edu/care/weeds-and-invasive-plants/mimosa-trees.html

4Reeves, W. (2010). “Invasive Plants – Cautions About Mimosa | Walter Reeves: The Georgia Gardener.” Walter Reeves: The Georgia Gardener | Gardening Tips and Advice from the Most Respected Garden Guru in the Southeast. Retrieved September 1, 2021, from https://www.walterreeves.com/landscaping/invasive-plants-cautions/.

5Dickinson, P. (2021, June 29). The Mimosa Tree: Beautiful But Invasive – Alabama Cooperative Extension System. Retrieved September 1, 2021, from https://www.aces.edu/blog/topics/forestry-wildlife/the-mimosa-tree-beautiful-but-invasive/.

6Trees.com Staff – last update on May 9, 2021. (2021, March 16). Mimosa Trees Buying & Growing Guide – Trees.com. Retrieved September 1, 2021, from https://www.trees.com/mimosa-tree.

7Pérez, J.(1990) Flore exotique dans les îles Canaries. Editorial Everest. Retrieved September 1, 2021, from https://en.wikipedia.org/wiki/Albizia_julibrissin#cite_note-4.

8Department of the Environment, W. (n.d.). Department of Agriculture, Water and the Environment. Retrieved September 1, 2021, from http://www.environment.gov.au.

9Albizia julibrissin (silk tree). (n.d.). Invasive Species Compendium. Retrieved September 1, 2021, from https://www.cabi.org/isc/datasheet/4005#touses.

10leoleobobeo. Pixabay. Retrieved from <https://pixabay.com/da/photos/red-mimosa-blomst-blomstre-plante-2410195/>

11AnRo0002. CC0 1.0 Deed. Public Domain. Wikimedia Commons. Retrieved from <https://commons.wikimedia.org/wiki/File:20170814Albizia_julibrissin1.jpg>