Removing Invasive Plants

Are any of these invaders still cluttering your yard?

A shrub with oval light-green leaves and bright red berries

Brazilian Pepper-tree, a showy invasive that has spread to over 700,000 acres in Florida. Image used in the 2014 Research Discoveries report. Photo: UF/IFAS File Photo

For many gardeners, their yard is their sanctuary. It's a place of peace and quiet in a busy world. Unfortunately, there may be trouble in paradise. Invasive plants are more than a threat to our ecosystem and economy. They're a threat to the tranquility of our landscapes.

In the world of horticulture, many invasive species begin as landscape favorites. That fabulous filler shrub may fill your garden, inch by inch and then row by row. Suddenly it's in your neighbor's yard, too! Worse still, over time they crowd out native species. This deprives native wildlife, like birds, bees, and butterflies, of food and shelter.

In the last 100 years over 50,000 plant and animal species have been brought to and established in the United States. About one in seven becomes invasive. Countless ornamentals listed as invasive are still in production, found wherever garden supplies are sold. They're attractive, and they don't come with warning labels or caution signs. So what's a gardener to do?

Take these three steps to remove problem species and restore tranquility to your garden: research, remove, and replace.

Step 1: Research

Before you pull out, share, or purchase a plant, always do your research. The University of Florida IFAS Assessment of Non-Native Plants in Florida's Natural Areas is an excellent resource for checking a plant's invasive status. The assessment includes pictures to help you identify the plant in question. The information is specific to North, Central, and South Florida.

Screen shot of the Assessment website showing a dropdown menu listing all the lantana species

A screenshot of the Assessment of Non-Native Plants in Florida's Natural Areas website.

But what about the anonymous plants in your garden? Sometimes even plant ID experts have trouble identifying a species. Other times it's been there so long you've forgotten a plant's name.

In these cases your best option is to contact your local Extension office for help identifying the plant.

Step 2: Remove

Once you've identified a problem species, it's time to remove it. With invasive species, this is often a challenge; they are, by nature, hard to remove. Generally, mechanical control methods (like pulling out the plant) should be tried before chemical control is attempted. Be sure to bag all plant debris and dispose of them in the regular, landfill trash. This keeps cuttings and seeds from establishing elsewhere.

Many tough ground-cover species can be difficult to remove by hand. In these cases, save your strength and let the sun kill them instead. In the hotter months of the year, cover the area with clear plastic. Then just bury the edges to keep it secure, and wait. This process, called soil solarization, is simple and inexpensive. After six weeks the plants underneath should be well and truly dead. Prolonged periods of cloudy weather may mean extending the treatment period, however.

Man spreading a clear plastic sheet over a garden bed

UF/IFAS researcher Bob McSorley demonstrates soil solarization. Photo: Tyler Jones, UF/IFAS

In extreme cases, a targeted application of herbicides may be necessary. Stumps of trees, for example, should always be treated with an appropriate herbicide to prevent regrowth.

Before applying a pesticide of any kind, it is important to educate yourself. Irreversible damage to your landscape is possible. Some herbicides are also toxic to humans. Reading and following all label instructions is required by law. Consult the Florida Homeowner Herbicide Guide for more information.

Do I really need to remove them?

One popular argument against removing problem species is that they are "well-maintained." Unfortunately, even when taking the utmost caution, an invasive in your yard can still spread. Some seeds may scatter in the wind. Birds can eat berries and then drop the seeds as they fly. The clippings might make it into storm drains and germinate hundreds of miles away. Invasive species cannot be managed perfectly, and all it takes is one escaped individual.

Please choose to remove invasive species. Your pet plant may be the next killer kudzu, monster hydrilla, or Brazilian pepper-tree. Early interventions are key when it comes to invasive ornamentals. While they're contained in your landscape there is hope, and it's in your hands.

Step 3: Replace

Once an invasive is removed, it's time to fill the hole. One fantastic resource for choosing replacement plants is the article series Alternatives to Invasive Plants Commonly Found in Florida Landscapes. These articles are region specific for North, Central, and South Florida. Each suggests dozens of replacements that deliver similar aesthetics to common invasive plants. Gardeners can choose from native species, non-invasive non-natives, and even sterile (non-fruiting) varieties. Many alternatives were bred right here at the University of Florida.

Lantana, for example, is a very popular landscape plant. Unfortunately, it is also listed as invasive in North, Central, and South Florida. The article linked above offers native replacement options, like beach sunflower, pineland lantana, and tropical sage. Also listed are a number of non-native but landscape-safe substitutes: African bush daisy, blue daze, rose, and autumn or scarlet sage.

shrub covered in clusters of tiny pink-red flowers and cluster of multi-colored flowers

'Bloomify™ Red', a sterile lantana variety. This is an excellent alternative to invasive varieties of Lantana camara.
Photo: Z. Deng, UF/IFAS

But for gardeners reluctant to lose their lantana, there is a third option: a sterile variety. Recently the University of Florida has released three sterile varieties of lantana: 'Bloomify™ Red', 'Bloomify™ Rose', and 'Luscious® Royale Red Zone™'. More are in production and coming soon.

Below is a list of some common invasive ornamentals still occasionally shared or found for sale. To learn more about these, and alternatives to the other plants on the list above, consult the article series on Alternatives to Invasive Plants linked at the bottom of this page.

Commonly Found Invasives

For help identifying landscape species and safely removing invasive species, contact your local extension office.

Also on Gardening Solutions

UF/IFAS Sites

UF/IFAS Publications

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