Continuous wet weather leads to the right conditions for Entomosporium leaf spot to develop on your Indian Hawthorne bushes. Look for small, reddish-purple dots on new leaves that seem to die in the center of the spots. Yellow outlines will form on the outline of the spots. Later you will see the leaves turning red and falling off. This leaves your Indian Hawthorne with a lot less leaves and looking really unhealthy.

This fungus lives on the leaves that are infected and also on the surface of the ground. If you catch it early, remove the infected leaves. Like most fungi, removing select branches and allowing more airflow will let the plant dry quicker. This creates a less pleasant place for the fungus. Also remove the old leaves that have fallen to the ground. 

Fungicides will help in controlling Entomosporium leaf spot. Use it about every two weeks when the weather keeps the area wet and the temperature is not hot enough to dry out the plant leaves quickly. Spring and Fall are prime time for this fungus to develop. If you continue to have problems with this disease year after year, consider replacing your plants with a different species.

​Vinca, aka periwinkle, is a super popular plant during Louisiana summers. The flower is everywhere you look and for good reason. The flower looks fantastic in Louisiana landscapes. It does well in hot weather and in drier conditions. Unfortunately wet weather and cool temperatures become the perfect environment for Phytophthora blight, the vinca killer. This disease is always present in the soil, but can affect vinca when conditions favor it for too long. It spreads easily by rain splashing onto neighboring vinca, causing crown and root rot. It can wipe out an entire planting in no time.

Here are some best practices for planting vinca: 

• Stick with newer varieties like Nirvana for example.
• Use thin a thin layer of pine straw mulch to prevent soil splashing.
• Do not plant vinca two years in a row in the same place.
• Rotate in a different flower every other year to reduce the active disease presence.
• Use periwinkle in pots with good drainage. Change the soil next year if you want to plant periwinkle again.
• Less is more when using irrigation. Vinca will die much sooner by over-watering than under-watering.

In the previous few years, boxwoods have been repeatedly damaged by an unknown source. Raj Singh, a plant pathologist from LSU AgCenter, noticed this and identified the cause as the fungus Colletotrichum. It causes random die-back of twigs and a black discoloration of the stem. There are currently no official recommendations for treatment for the fungus. Considering this, take extra care to sanitize your pruning equipment to prevent the spread of the disease to healthy plants. If you suspect your boxwoods have been infected, please contact your AgCenter extension. Removal of infected plant matter may help prevent the spread of this new pathogen.

It is the middle of the summer and your crepe myrtles leaves are starting to discolor. They are developing brown spots and the leaves change from their natural green to yellow, orange and red. Crepe myrtle leaves will start to fall and your tree will start to look pretty shabby. So what is causing this problem?

Cercospora Leaf Spot is a fungus that causes all the problems mentioned earlier. While it won't severely damage your tree at first, it will return each year can start hurting your tree.  The fungal spores spread from splashing water during warm wet weather. Trees in humid areas with little air flow are more severely affected.

Buy a fungicide labeled for Cercospora Leaf Spot. Treat your tree as specified on the label starting in early summer when you first notice new spots. Most products have a short control period. If so, you will need to retreat your tree every one to two weeks, depending on the product label. Thinning the branches on the crepe myrtle will lead to better airflow and reduce the chance of Cercospora Leaf Spot recurring.

GreenSeasons offers fungus control and professional pruning in the greater Baton Rouge, greater New Orleans, Slidell, Prairieville, Walker, Denham Springs, Gonzales, Baker, Zachary, Hammond and Covington areas. If you need fungus control or professional pruning, click here for a free quote and we will give you a call. 

If you would simply like some advice on fungus control or pruning, please contact us and we will be more than happy to help.