Gardening Questions And Answers
Diseased coreopsis plantings turn yellow and fail to grow properly, while the flower heads appear in greater numbers than usual. The petals on the flowers are deformed or greenish. Slow the spread of the disease by removing any infected flowers as soon as you notice them, and keep the area free of weeds.
Where to Plant Coreopsis. Regardless of the type you’re growing, coreopsis need full sun, so plant them where they will receive at least 6 to 8 hours of sunlight per day. Coreopsis grows best in well drained, moderately moist soils. These are not good plants for a poorly drained, low spot in the yard.
Powdery and Downy Mildew Powdery mildew is a disorder that occurs when coreopsis plantings become infected with the Sphaerotheca macularis fungus. A white powdery substance appears on the upper side of the leaves. Powdery mildew does not usually kill plants, but it significantly reduces their aesthetic value.
Coreopsis is a hardy plant suitable for growing in USDA plant hardiness zones 4 through 9. As such, coreopsis winter care isn’t a difficult task, but a bit of protection will ensure the plant remains hale and hearty throughout even the toughest winter, ready to burst forth when temperatures rise in spring.