The striking blossoms of oriental poppies (Papaver orientale) adorn frilled, blue-green leaves. Recommended for U.S. Department of Agriculture plant hardiness zones 3 through 9, this herbaceous perennial is typically void of problems associated with diseases or pests. However, when it comes to cultivation, the blooms and other growth can decline if needs aren't met.
1. Oriental Poppy Flowers
Oriental poppies bloom from May through June with papery flowers in shades of red, orange, pink, white and even bi-colored. The flower stalks can be up to 3 feet tall and should be staked if you are worried about them breaking under the weight of the flower. Although diseases and pests are not a large risk, improper care can impair the health of the plant and can invite diseases. Maintaining healthy plants is the best method of protecting your plants from problems and encouraging flowers to bloom.
2. Cultural Requirements
Oriental poppies perform best in a sunny location with moist, well-drained soil. They do not tolerate extreme heat and will die back to the ground during the summer months. New growth will arise during the fall. Plants should be spaced 2 to 3 feet apart to allow proper air circulation. To extend the bloom season, remove flowers from the plant when they are done blooming. Remove weeds as they appear to avoid competition for water and nutrients.
Soil that does not drain readily can easily become over-saturated. This eliminates the amount of oxygen the plant roots can uptake and can negatively effect the functions of the plant including flower production. Nutrient disorders can hinder flower production as well, but this relates back to the condition of the soil. Necessary nutrients may be in the soil, but inaccessible by the plants if the soil condition is poor. A soil test can help you determine the pH level of the soil as well as the available nutrients. Typically, a pH between 6.0 and 6.5 is appropriate for growing perennials. Knowing the conditions of your garden soil can help identify problems that may be preventing your poppies from flowering.
Botrytis blight is a fungus that can harm the flowers of poppies. Flowers may show symptoms of discoloration, buds may rot or even fall from the plant before opening. Although diseases are not common with oriental poppies, they can be present especially in areas with high humidity. Proper plant spacing and removing debris from the soil around your plants can reduce the risk of disease.