Photo courtesy of Kinsey Watkins
Pansies originated in Europe and are a part of the viola genus. The pansies we know today were bred from the wild pansy, Viola tricolor. A typical flower has purple upper petals, white lateral petals, yellow flower petals, and several purple veins in the flowers throat. Cultivation of the modern day pansy began in the early 1800s in Iver, Buckinghamshire, England. In 1839, William Thompson discovered the first pansy with blocks of color on the lower petals now known as a ‘face’; it was named ‘Medora’. By about the turn of the 20th century, ‘clear color’ pansies, pansies without faces, were developed. In the last 50 years, new pansy colors such as shades of pink, orange, and unusual biocolors have been developed.
With their wide array of colors and their cold hardiness, pansies are a great addition to your cool season annual plantings. There are a few key considerations when planting pansies including temperature, location, fertility, and pests and diseases.
Temperature: The optimal time to plant pansies in this area is late October through early November. Pansies do best when nighttime temperatures are consistently below 65° F. Soil temperatures should be between 45° F and 65° F. While pansies are known for their ability to bounce back after frost or freezing temperatures, if plants are planted too late they will not have enough time for roots to establish before winter. When soil temperatures are too cold during planting, stunting, yellowing of leaves, and poor flowering can be observed. On the other hand, when pansies are planted too early, when it’s too warm, yellowing and stretched stems are common. These plants can be more prone to diseases and insects.
Location: Planting location is critical to the health and vigor of your plants. Pansies should be planted in full sun, getting 6 to 8 hours a day. They also will not tolerate wet feet, make sure your bed has good drainage. After planting and at the beginning of the season when days are longer, plants will need more water than when days become shorter and the temperatures are cooler. Make sure you adjust your watering to accommodate these conditions. Mulching will not only help conserve moisture levels, but will insulate the roots during cold snaps. To further help with cold hardiness, always water your flower beds and containers before prolonged cold spells.
Fertility: For best growth, test soil to determine nutrient and pH levels. Pansies grow best between a pH of 5.4 and 5.8. Choose a slow release fertilizer and split apply it at least twice throughout the season starting at planting. Avoid fertilizer with high nitrogen levels because it promotes stretching and succulent growth during warm fall weather which weakens the plant and makes it more susceptible to winter injury.
Pest/disease: Deer are among the most common pests for pansies. Avoid planting them where they are easily accessible to deer. Aphids, spider mites, pansyworms and slugs are another common pest to look out for.
Common diseases found in pansies are crown and root rot, botrytis, downy mildew, and leaf spot. Crown rot is caused by a soil-borne fungus called Phytophthora parasitica. It is most common in the spring and fall because of the wet, warm weather. The fungus infects plants at the soil line and plants will wilt and die. When dug up, the roots will be brown, water-soaked, and mushy if they are present at all. Botrytis is an airborne fungus that is spread through dead or damaged plant material. Downy mildew consists of light-colored blotches with gray spores on the underside of leaves while the top of the leaf may look chlorotic. If conditions persist the spores congregate and a fuzzy, gray texture will form. Several leafspot diseases can infect pansies. They vary in color from white to black. Spots may have a dark brown border or halo. While leafspots are common they seldom cause significant damage. There are several cultural practices that can reduce the risk of these diseases such as keeping beds clean of infected plants and debris, buying healthy plants, proper fertility and pH, letting the soil dry slightly between waterings, rotating plantings, and sanitizing tools.
With all the fun colors, ease of care, and winter beauty, pansies are a wonderful addition to any planting.
For more information about landscape gardening, contact N.C. Cooperative Extension, Richmond County Center at (910) 997-8255. In addition, follow us on Facebook or visit our website for upcoming events and up to date information.