Structural Adaptations of the Periwinkle

Vining Habit

• Periwinkle can grow in many locations due to its tolerance for a variety of soils. It is also not vertically limited as the plant will gradually build up on top of itself and rise upward. It is not self-climbing but can become self-supporting over time. The Vinca can also cascade downward without any extra support for the stems. This makes it an excellent hanging plant in baskets and planters. The stems can grow many feet without needing the support of soils.

Stolens

• The stems of Vinca have stolens with internodes along them, which are growing points. As the stems spread along the ground, each internode has the ability to root into the soil. This gives rise to more plants and creates a tenacious mat of growth that helps prevent weeds and conserves moisture. Periwinkle can be started from cuttings that include an internode. The stems root easily when cut just above a growing point. This adaptation adds to the plant's reproductive strategy of seed and division.

Stems and Leaves

• Vinca rises from a crown that may sprout numerous branches or stems. The stems start out succulent but mature to a woody texture with light bark on the exterior. This makes the plant capable of withstanding light foot traffic and enduring winds and moderately harsh conditions. The leaves of periwinkle have a waxy coating and are semi-evergreen to evergreen. The waxy coating helps preserve moisture while the leaves have the capacity to drop in extreme temperatures. This physical attribute helps preserve the plant's core by preventing conductive cold damage.

Root System

• Periwinkle makes an excellent erosion control and ground cover because of its extensive root system. The roots can grow in almost any soil and spread widely. The roots are fibrous and create an underground web that stabilizes the soil and anchors the plants. Periwinkle is very hard to pull out of the ground and its roots are often left behind. New plants easily grow from root fractures left in the soil. Vinca is not destroyed by disturbing soils, due to the wide root system.