Japanese honeysuckle (Lonicera japonica) is a common, fast-growing vine with fragrant flowers. Introduced from East Asia in the early 1800s, this perennial woody vine can reach 30 feet or more.
Understanding Japanese Honeysuckle
Japanese honeysuckle is a woody vine with fragrant flowers that are initially white, fading to creamy yellow, and bloom from late spring through fall. Small, dark purple to black berries ripen from September through November.
This vine spreads aggressively through sexual and vegetative means. Seeds are dispersed, while vegetative reproduction occurs via rhizomes and runners. Its rapid growth forms dense thickets, outcompeting native plants for resources. It can climb and smother trees.
Controlling Its Growth and Spread
Managing Japanese honeysuckle requires persistence and combined methods. For small patches, hand-pulling is effective, ensuring the entire root system is removed. Pulling works best in moist soil before fruiting. Cutting exposed stems weakens plants in larger infestations. Mowing large areas twice yearly can slow spread.
Systemic herbicides like glyphosate or triclopyr control the plant by moving to the roots. Foliar sprays can be applied from spring through fall. Fall application is recommended to minimize harm to non-target plants. A 1.5-2% glyphosate foliar spray effectively eradicates Japanese honeysuckle.
For cut-stem treatment, apply a 25% solution of glyphosate or triclopyr to freshly cut stem surfaces. This method can be used year-round if the ground is not frozen. Always follow label instructions for chemical application and safety.
Pruning limits vigor and spread, though it’s often insufficient for eradication alone. Vines can be cut to prevent climbing and girdling other plants. For maintenance, prune yearly after flowering. For overgrown plants, perform a more aggressive prune in late winter or early spring when dormant, removing older, woodier stems. Never remove more than one-third of the vine, and avoid severe pruning more than once every two to three winters.
Long-Term Management and Monitoring
Effective management of Japanese honeysuckle requires ongoing vigilance and consistent monitoring for regrowth. After initial control, plants will likely resprout, requiring follow-up. Regular inspection helps detect new growth early for prompt intervention.
Consider planting native alternatives where Japanese honeysuckle has been removed. Native plants outcompete invasive species and aid ecological restoration. Replacements include trumpet honeysuckle (attracts hummingbirds) or Virginia creeper (for groundcover). Other native options are available.
Safe Disposal of Removed Material
Proper disposal of removed Japanese honeysuckle material prevents re-rooting and seed dispersal. The plant readily regrows from small stem or root fragments. Leaving cut vines on the ground or adding them to compost without proper treatment can lead to new infestations.
Effective disposal methods include:
Bagging for landfill disposal prevents re-rooting.
Solarization: sealing plant material in clear plastic bags in direct sunlight kills viable parts and seeds.
Burning destroys plant material, including seeds, where permitted and safely.
Composting: only if the pile consistently reaches 145 degrees Fahrenheit for 30+ days to kill seeds and root fragments; otherwise, do not compost.