How To Kill Trumpet Vine

Campsis radicans is the Trumpet Vine. It is a vigorous grower in many parts of the United States.

This woody vine is quite lovely, and the flower clusters are very attractive to butterflies. This wild and luxuriant vine can become quite invasive in ideal settings throughout USDA zones 4-10.

Orange-red Campsis grandiflora trumpet vine flowers in the gardenPin
Bright Colored Campsis Flower | Olivia-DepositPhotos

Native to southeast North America, this vine grows well in most soil conditions, especially in forests or swamp environments. 

Botanical Name: Campsis radicans 

Common Names: Trumpet vine, trumper creeper, hummingbird vine  

Trumpet vine grows well in pollinator gardens, as it attracts hummingbirds. The self-seeding nature of this plant makes it invasive in most environments. 

The entire trumpet vine is mildly toxic for people and pets, especially the seeds, foliage, and sap. 

In this article, we share tips on keeping your Trumpet Vine under control and on eliminating it if needs to be.

Keeping Your Trumpet Vine Under Control

If you don’t have a Trumpet Vine now, you should plan before thinking about getting one. To keep it under control, it is best kept as a container plant.

Trumpet vines grow in most soil conditions, including clay, loamy, and sandy. Keep vines in moist but well-draining soil similar to their native environments in forests or swamps. Water Trumpet vines are relatively drought-tolerant.

Some gardeners believe the trumpet vine can grow “controlled” in a submerged container. This makes the plant appear as if it is growing directly in your garden. This is a risky proposition.

If a single root or tendril escapes the container, the plant can soon run rampant. During droughts, some fertilization might help trumpet vines to continue growing.

Do you already have a Trumpet Vine planted in your garden?

You may be able to keep it under control by digging a trench around it every early spring.

The moat should be about a foot wide and a foot deep. It should circle the plant about three feet away from the main stalk all the way around.

Trumpet Vine appears after several months of warm weather, so the bloom time is during the summer. The Trumpet Vine produces trumpet-shaped flowers, covering a fence or wall in beautiful orange blossoms. 

You can curb your plant’s growth with frequent pruning. Snip or mow shoots when they appear in unwanted areas. 

This will not kill the plant but will at least provide the illusion of some measure of control. This vine will grow in partial shade but produce the most blooms in full sun.

The sap contains oxalate crystals, which can cause skin irritation or rashes. Wisteria is usually only harmful to adults if ingested in large quantities. 

5 Potential Ways To Kill A Trumpet Vine

If you and your Trumpet Vine have a hate/hate relationship, you may want to kill it. Like getting rid of Poison Ivy, this is not an easy matter! Trumpet Vine spreads fast through an extensive root system.

The most toxic interaction you can have with an angel’s trumpet is eating it, which can cause symptoms ranging from intense thirst to coma. 

No matter what you do, you may find that far-flung roots are very likely to spring up in surprising places.

Here are five techniques you can try, together or combined, to do away with your Trumpet Vine.

Spray The Leaves With A White Vinegar Solution

To use the vinegar method:

  • Mix white vinegar and water half-and-half in a spray bottle.
  • Cut back as much of the vine as you can
  • Spray what’s left of the vine and leaves with your vinegar mixture.

It’s best if you do this on a bright, hot, still sunny day. The bright sunlight helps the vinegar to kill the leaves. Be careful when spraying this mixture because it will kill anything it touches.

Full sun, meaning at least six hours of direct sunlight on most days, will produce the best flowering. Soil These vines can tolerate a wide range of soil types,

Dig Up All Of The Roots

If you want to kill the plant, you’ll need to remove the roots completely. This may be an impossible task.

Any tiny part of the root left behind will start growing a new plant.

After you remove all of the roots, you may see baby Trumpet Vine springing from the ground. When this happens, you must pull them up and dig up as much of the root as you can find.

Poison The Stump

Chop the vine down to ground level and apply undiluted glyphosate herbicide to the stump. Paint it on rather than spray it.

Avoid overspray of herbicides in your garden. If you apply an herbicide on a windy day with a sprayer, you can do a great deal of damage to your favored plants.

Repeated herbicide applications painted directly onto the stump can kill the roots. As with all other methods of killing Trumpet Vine, you must be diligent.

Apply the herbicide frequently and check all around for signs of new growth.

Throw Boiling Water On It!

To avoid using chemicals, try scalding your Trumpet Vine with boiling water.

The Boiling Water Method

  • Cut the vine back to the ground
  • Drench the soil to a distance of three feet all the way around the plant with boiling water.
  • This method will take a lot of boiling water
  • It needs to be done quickly, so be prepared!

You want to be safe and careful. Don’t toss the boiling water! Pour it slowly at ground level. This will help keep it as hot as possible and will avoid waste and danger.

As with the other methods, boiling water control is not guaranteed.

You will need to keep checking for shoots springing up in unexpected places. When you find them, you can yank them up, dig them up and/or douse them with chemicals, vinegar, or boiling water.

Salt The Earth

If you hate your Trumpet Vines, you can mix a cup of rock salt in with each gallon of boiling water. This method is discouraged!

Salting the earth is a practice maligned since biblical times. As with herbicides and vinegar, salt does not discriminate.

It will kill any plants it comes in contact with, and it will ruin the soil for quite a while to come. Even so, your Trumpet Vine can escape the treatment since it has already sent roots far away!

Trumpet Creeper: Cautions

Be Committed To Get Rid Of Trumpet Vine

Trumpet Vine is persistent, so you have to be persistent too. You can use one or a combination of all of the above methods. Realize that none of the methods will be effective unless you stay focused.

According to North Carolina Extension Gardener, the fruit, foliage, flowers, and sap are toxic and can cause mild to severe skin rashes and irritation if handled. 

Wear gloves when pruning and wash your hands immediately after handling any portion of the plant. 

You must keep checking back and applying one measure or another to fight off the Trumpet Vine.

No matter what methods you choose, be sure to stay safe.

When handling dangerous materials, such as boiling water and chemicals, wear eye protection, gloves, protective shoes, long sleeves, and pants.

Work carefully, and only apply the treatments to the targeted plant.

Angel’s Trumpet Poisoning in Dogs

Since this plant produces pretty flowers, many people have it, not knowing how toxic it actually is to their pets. 

 Its tendrils grab onto every available surface and become thick, heavy stalks as they mature. This plant causes minor contact dermatitis and mild toxicity if eaten.  

The flowers are large and showy and produce a distinct fragrance. The leaves do give off a pungent smell which keeps most pets from nibbling on it, but not all pets. 

If you suspect that you or someone you love has accidentally ingested a poisonous plant, call the poison control center immediately, and if necessary, seek emergency medical attention.

All parts of the angel’s trumpet plant — including the flower, leaves, seeds, and stem — contain a toxin called scopolamine that can cause serious poisoning to humans and pets. 

In addition to eye dilation and blurry vision, other symptoms can be caused by exposure to the toxin, especially if the plant is ingested, includes:

  • Muscle weakness
  • Dry mouth
  • Rapid pulse
  • Elevated temperature
  • Urinary retention 

“The seed pods and flower pose the greatest risk of accidental poisoning as they are not only visually appealing to children and pets, but they also contain the highest concentration of the toxic compounds,” says Dr. Villano.    

According to the literature, the most common symptoms of angel trumpet poisoning include:

  • Dilated pupils
  • Blurred vision
  • Gastroparesis bloating
  • Muscle weakness
  • Fever
  • Hallucinations
  • Paralysis
  • Rapid heart rate (tachycardia)
  • Memory loss
  • Respiratory failure
  • Emotional changes
  • Mental changes

Many of these symptoms vary in severity depending on how much of the plant was ingested.  

If your dog is having seizures, the veterinarian will give an anticonvulsant medication to stop them. 

If your dog is vomiting uncontrollably with no production, they will give an antiemetic, and if your canine is constipated, the team will give medications or perform an enema if needed. 

If your pet is experiencing behavior changes or disorientation, use caution when approaching and handling the pet; they may become aggressive due to the toxin. Keeping him in a calm, quiet place will help with this.

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