Fusarium wilt is a fungal disease that affects a wide array of plants including vegetables, trees, perennials and shrubs. The fungus, Fusarium oxysporum, is soil borne and usually enters plants through openings in the roots. It tends to be very persistent in the soil so plants that are diagnosed with fusarium wilt or rot need to be removed and destroyed. Then, they should only be replaced with plants that are resistant to the disease.

As the name implies, the key symptom of this disease is a wilting of foliage and twigs. This usually occurs starting in late summer when the days are hot and dry. Because of the disease, the plant is not able to keep up with the evaporation demands resulting in wilt. The leaves will turn yellow and have a scorched appearance around the edges. Plant growth will be stunted and, eventually, major parts or all of the plant may die.

As a post-mortem indication of fusarium wilt, there is often a discoloration of the vascular tissue in small to medium sized branches. This stain may be seen in a cross section of the branch cut. This symptom is common to most of the various wilt diseases.

There are a couple of ways to help prevent the occurrence of fusarium wilt in the home landscape:
 
  • Resistance - If fusarium wilt has been a problem with plants in the landscape, they should be replaced with species that are resistant. Since the disease is soil borne, it sticks around from year to year.
     

  • Prevent Root Damage - There needs to be some sort of opening in the roots of the plant for the fungus to enter from the soil. Sometimes this will happen through the alternate freezing and thawing of the soil which may damage the roots. At other times, activities such as nearby construction, using heavy equipment over the root zone or soil excavation provide an entry point.


1. Remove and Discard Infected Plants

2. Inspect Bulbs - Inspect your bulbs, corms, tubers and rhizomes before planting and destroy those that are soft and rotted or have a distorted form. Do not put them in the compost pile.

3. Chemical Controls - Prevention is the key since there really are no practical chemical controls for fusarium wilt in landscape plants. In rare cases, soil infected with fusarium may be sterilized with harsh chemicals but this is only done in commercial nurseries.

Note: We have provided some general information and observations on this topic aimed at the home gardener. Before you take any serious action in your landscape, check with your state's land grant university's Cooperative Extension Service for the most current, appropriate, localized recommendations.


 
Some flowering plants susceptible to fusarium wilt:
Antirrhinum - Snapdragon
Astilbe
Browallioa
Caillstephus - China Aster
Campanula - Bellflower
Centaurea - Bachelor Button
Chrysanthemum - Mum
Cosmos
Cyclamen
Dahlia
Delphinium
Dianthus - Pink, Sweat William
Digitalis  - Foxglove
Lantana
Lilium - Lily
Matthiola - Stock
Narcissus - Daffodil
Paeonia - Peony
Senecio - Cineraria
Tagates - Marigold
Tulipa - Tulip

 

Copyright 2000-