Wild Cucumber Invasion

By Vijai Pandian, Horticulture Educator

Wild cucumber grows so quickly it can completely cover bushes and trees.

Wild cucumber plants have 5 pointed leaves and white flowers. They can grow 25-30 feet in a season and easily encompass other plants.

All plants, including weeds, are conspicuous in the natural landscape at a certain season. In early autumn, one such attractive weed that has begun to catch attention in southeast Wisconsin is wild cucumber (Echinocystis lobata).  Native to Wisconsin, wild cucumber is a fast-growing annual vine that grows along roadsides, ditches, streams, and riverbeds. This climbing vine forms dense patches of entangled leaves and tendrils that can engulf large trees and shrubs and can grow to a potential of about 25-30 feet in a season. Luckily, this vine dies off in the fall.

During late summer, wild cucumber produces greenish-white blossoms that adorn the tops of trees and shrubs. The leaf of wild cucumber looks like maple, with 5 triangular pointed lobes, and has 3 forked coiling tendrils that arise from the leaf axil. In fall, it produces inflated green oblong fruit pod with spines on its skin. Despite sharing a name with other cucumber plants, the fruit is nonedible. When it ripens, the pod turns papery brown and cracks at the bottom to drop its seed. Its attractive pods are used for dry flower arrangements, but be careful of its spines.

Wild cucumber is a vine with 5 point leaves and white flowers. The white flowers grow into seed pods with spines.

Wild cucumber is a vine with 5 point leaves and white flowers. The white flowers grow into seed pods with spines.

Though wild cucumber is a native species, its aggressive nature can smother other desired plant species in natural areas.  Spraying with herbicides can be difficult, due to potential drift injury on desired plants.  One of the best ways to control is to find the main stem that arises from the ground and sever it close to the ground.  Another similar species to wild cucumber, but less common, is bur cucumber.  Next time, when you spot an aggressive vine with a creamy green flower, take a closer look to check for wild cucumber.

For more gardening info or plant-health related questions, contact us at planthealth.advisors@extension.wisc.edu