The trumpet vine (Campsis radicans) is a vigorous, woody perennial often sought after for its attractive, tubular orange flowers. While beautiful, this plant is notorious for its highly aggressive, invasive nature once established. Successfully removing an established trumpet vine requires more than simple pruning; it demands a persistent, multi-season approach to ensure complete eradication. This guide focuses on both physical removal and targeted chemical intervention for managing this challenging plant.
Understanding the Vine’s Aggressive Growth
The difficulty in killing the trumpet vine stems from its robust underground structure, which allows it to recover from almost any damage. Established vines possess deep, thick, woody taproots that store substantial energy reserves, allowing the vine to quickly regenerate new growth even after the above-ground structure is removed. Campsis radicans also spreads extensively through lateral runners, which are underground stems known as rhizomes. These runners give rise to numerous new shoots, or suckers, far from the original location. Even small, overlooked fragments of these runners or the taproot are capable of sprouting a new vine, making physical removal alone challenging.
Non-Chemical Eradication Strategies
Cut and Dig Method
For individuals preferring to avoid chemical treatments, the primary strategy involves physical removal of the extensive root system. The “Cut and Dig” method targets the main taproot and lateral runners, requiring careful excavation of the soil around the main stem. It is important to trace the lateral runners as far as possible, removing every section, since missing even a small piece can lead to rapid regrowth.
Smothering and Solarization
Another method focuses on depriving the plant of the sunlight it needs to photosynthesize. Smothering or solarization involves cutting the vine back to the ground and then covering the entire area with thick black plastic or a heavy layer of mulch. This covering should remain in place for at least one full growing season, often two, to effectively starve the deeply stored root reserves.
Continuous Cutting
A longer-term strategy is continuous cutting, aimed at exhausting the root system over multiple seasons. This involves repeatedly severing the vine near the ground as soon as new growth appears, preventing the leaves from maturing and contributing energy back to the roots. Consistency is important, as any period of unchecked growth allows the root system to recover its stored carbohydrates. This approach typically requires persistent monitoring for two to three years.
Systemic Herbicide Application Techniques
For established and aggressively spreading trumpet vines, chemical intervention using a systemic herbicide often provides the most reliable path to complete eradication. Systemic herbicides, such as those containing glyphosate or triclopyr, move throughout the plant’s vascular system into the deep root structure. The most effective time for application is in the late summer or early fall, when the vine naturally begins translocating sugars and resources downward to the roots for winter storage.
Cut-Stem/Paint Technique
The most precise method is the “Cut-Stem/Paint” technique, which minimizes environmental impact and protects surrounding vegetation. Begin by cutting the main vine stem about one to two inches above the soil line. Immediately, a concentrated systemic herbicide must be applied directly to the fresh, exposed outer ring of the stem, known as the cambium layer.
This timing is crucial because the plant’s vascular tissue quickly seals off, preventing absorption if a delay occurs. Concentrated products, often 41% glyphosate or greater, are painted directly onto the cut surface using a small brush or dedicated applicator. This targeted approach ensures the chemical moves directly into the root system without affecting nearby plants.
Foliar spray application is generally less effective for established vines and carries a significant risk of drift and runoff, potentially harming non-target plants. When handling concentrated herbicide, follow all manufacturer instructions regarding personal protective equipment. Gloves, eye protection, and long sleeves should be worn to prevent skin contact or inhalation.
Furthermore, any tools used for application should be thoroughly cleaned or dedicated solely to herbicide use to prevent accidental contamination of other plants or surfaces.
Managing Suckers and Preventing Recurrence
Eradication does not end with the death of the main vine, as the extensive root network produces new shoots, or suckers, for months or even a year afterward. Successful removal requires consistent monitoring of the area for one to two years following the initial treatment. New growth must be addressed immediately to prevent the root system from regenerating energy reserves.
Suckers can be managed either through repeated physical cutting or targeted chemical applications. Repeatedly cutting the new shoots to the ground will deplete the remaining root energy. Alternatively, applying a low-concentration systemic herbicide directly to the leaves or the freshly cut stem provides a more rapid solution. For chemical treatment of suckers, a small cotton swab or sponge can be used to carefully wipe the herbicide onto the leaves or the cut stem, ensuring local absorption.