The Leaves Are Turning Yellow on My Annual Periwinkle

Annual Periwinkles

• Vinca minor grows to 6 inches and features small, 2-inch-long leaves. Vinca major, another periwinkle cultivar, grows to a greater height, with 3-inch-long leaves. Both cultivars feature small, blue-purple flowers and grow as ground covers or climbing vines.

Season

• Periwinkle is a frost-sensitive plant and grows only during spring and summer. Yellow leaves in early spring or fall signify low temperatures and frost. Fall brings the end of a periwinkle vine's lifetime in most zones.

Sun and Air

• Periwinkle grows in full sun but prefers partial or dappled shade. Too much bright sun leaches color from periwinkle leaves. Deep shade, on the other hand, restricts photosynthesis and chlorophyll production and may also lead to wilted, yellow leaves.

Soil, Nutrition, Water

• Periwinkle vines prefer relatively rich, moist and quick-draining soil. The Iowa State University Extension notes that periwinkle turns sickly and yellow in wet, sticky soil and recommends soil amendments to encourage drainage. Turn organic compost into a planting site to give periwinkle vines nutrition and drainage. The Clemson Cooperative Extension recommends adding 10-10-10 fertilizer at planting to give periwinkle the nutrition it needs for growing. Water periwinkle vines with 2 inches of water every week to keep it moist and healthy.