Have you been troubled with your prize iris buds turning brown and mysteriously dying? The chances are that Iris crown rot may be the culprit. Unfortunately, some of the iris hybrids are more severely attacked than the older varieties.
Iris Crown Rot
Above-ground symptoms of crown rot vary somewhat depending on the particular organism causing the trouble. Wilting, the iris leaves turning yellow, wither and dying, start when iris are in bloom.
The leaves may collapse suddenly or gradually die back from the tips. When underground parts are dug up, the rhizome and leaf bases may be slimy and foul-smelling (soft rot) or shriveled, dry, and rotted (dry rot).
Soft rot is caused by bacteria that commonly enter the iris plant through feeding wounds made by iris borer worms. Rotting is often rapid in older beds which are overcrowded, shaded, and poorly drained.
Dry rot may be caused by one of a half dozen or so fungi. Fungus threads or mold growth may often be seen on rotting plant parts if the soil is moist. Decayed and shriveled rhizomes often fail to grow shoots in the spring, or the shoots which do appear are weak and soon die.
Related: Iris Blooming Season
What To Do When Iris Flowers Die – Control Soft and Dry Crown Rot With These Steps:
- Plant only firm, healthy rhizomes or bulbs, as shallow as practical, in well-drained soil and in a sunny spot where iris has not grown for the past three years. Allow plenty of space between clumps.
- Spray weekly, starting when the new leaves are two to four inches tall
- Use a good all-purpose fungicide like Bayer Advanced Disease Control for Roses, Flowers, and Shrubs or Ortho Garden Disease Control.
Follow up with a spray of Orthene or Isotox Formula 4. Spraying should continue until iris plants are full-grown.
Orthene and Isotox Formula 4 should control the iris borer and other chewing insects while the Ortho and Bayer Disease Control products control leaf spot diseases.
The addition of a half teaspoonful of household soap or detergent to each gallon of spray will aid in wetting the glossy foliage. - When iris crown rot first strikes, drench the soil around infected plants with Bayer Advanced Disease Control for Roses, Flowers, and Shrubs or Ortho Garden Disease Control·
Use one pint on each square foot of bed surface to be treated. Repeat in 10 days. If rot continues, take up the rhizomes after flowering. Cut out and destroy all rotted portions. Soak the remainder in the Bayer or Ortho solutions as stated on the label. - Dig up and divide clumps every third year to avoid overcrowding.
- Remove and destroy any infected leaves, cutting back the remainder to 5 to 6 inches. Destroy old plant tops and other plant debris. Avoid cutting or bruising underground parts when digging or cultivating.
Wounds make easy entrances for crown rot-producing organisms; after digging and separating, dry clumps thoroughly for several days were cool and dry. Throw away any rotted ones.
If these steps are followed, crown rot should disappear as well as many of the other pests which mar the beauty of this outstanding garden flower.
Related: Learn More About How To Keep The Iris Healthy and Beautiful
More On Why Are My Iris Turning Brown?
Let’s assume your Siberian Iris is experiencing some issues, and some have died. Nobody likes to hear of an iris dying!
Why are my iris flowers dying? Why do iris leaves turn brown and the eventual death of your Iris plants is concerning. Here are some possible explanations for these dying flowers and brown leaves.
Browning of Your Siberian Iris could be from Environmental Factors:
- Irises generally thrive in full sun or partial shade.
- Make sure your Iris plants are receiving adequate sunlight.
- Check if your iris are planted in well-draining soil to prevent waterlogged soil
- Excessive moisture can lead to root rot and the decline of the plant over time.
Consider the Care and Maintenance of your Irises
- Regular watering, especially during dry periods, is crucial to keep the plants hydrated.
- Avoid overwatering it can lead to root issues.
- Finding the right balance is essential for the health of your Iris plants.
Pests and Diseases Affect the Well-Being of Your Iris Plants
- Keeping an eye out for symptoms such as discoloration, wilting, or unusual growth can help you identify potential problems.
- If you notice any signs of infestation or disease, consult with a local gardening expert
- Or take appropriate measures to fix the issue.
If the tips of your Siberian Iris leaves are turning brown and the plant appears to be dying, assess the environmental conditions, watering practices, and potential presence of pests or diseases. Identifying the underlying cause can help you take the necessary steps to revive your Iris plants and ensure their vibrant beauty in your garden.