Can a Periwinkle Plant Live in the House for the Winter?

Sunlight

• Periwinkle plants grow well in outdoor locations with full to partial sun exposure. When overwintered indoors, provide periwinkle with as much sunlight as possible. Position your plant within 4 feet of a south- or west-facing window that receives a minimum of four, but preferably six, hours of direct sunlight per day. If you are unable to provide periwinkle with at least four hours of daily sunlight, use grow lights to supplement the natural light it receives.

Temperature

• Simulate periwinkle's ideal climate in your home to ensure healthy winter growth. Periwinkle requires daytime temperatures between 72 and 80 degrees Fahrenheit to grow and bloom successfully. Expose periwinkle to temperatures that are 7 to 10 degrees cooler at night; this mimics the cooler nighttime temperatures that they enjoy outdoors. Consistency is key to successfully overwintering your periwinkle; program your home thermostat to provide these same temperatures every day.

Irrigation

• Periwinkle prefers consistently moist soil during the spring and summer. In the winter, it's best to let the surface of the soil to dry to the touch between each irrigation. Water periwinkle thoroughly each time you irrigate; hold the planting container under cool, not cold, running water until you see it dripping from the drainage holes. Make sure that all of the excess water drains free of the container; soggy soils may cause the roots of your periwinkle to rot.

Fertilization

• Periwinkle needs weak, but frequent, applications of fertilizer during its time indoors. Feed periwinkle with a quarter-strength solution of a balanced, water-soluble houseplant fertilizer every two weeks. Because improper fertilization can do more harm than not fertilizing at all, always consult the application instructions on the fertilizer packaging before fertilizing your periwinkle plant. Fertilize periwinkle with a single application of a water-soluble, high-phosphorus fertilizer before moving the plant back outdoors in the spring.