tendrils

Tendrils are slender, curling plant structures that enable climbing and anchorage. They are specialized organs that arise from various plant parts and can be modified leaves, leaflets, stems, or inflorescences. Tendrils are widespread among climbing plants, including many in Fabaceae (peas), Vitaceae (grapes), and Passifloraceae (passionflowers). In peas, tendrils are modified leaflets at the end of the leaf, forming a spiraling appendage that grasps supports. In grapes, tendrils typically arise opposite the leaf and are modified shoots that coil when they touch a support. In passionflowers, tendrils originate from leaf axils and are often branched, enabling multi-point attachment. Other plants may use stem tendrils or tendrils derived from stipules.

Tendrils function through thigmotropism: touch or contact triggers differential growth that causes the organ to coil around supports. This behavior allows the plant to ascend with minimal structural investment, placing leaves and bearing structures higher where light is more available.

Structurally, tendrils are usually slender, flexible, and rich in vascular tissue, and they may be reinforced with sclerenchyma for strength. Some tendrils coil in a regular spiral, others form a clamp or hook, depending on species and environment.

The term tendril comes from Latin tendere, to stretch, reflecting their role in reaching and grabbing supports in the plant’s climb toward light.