Wet Weather Diseases
Summer may officially be here, but it has been wet! Did you know that plant-borne diseases can spread through rainwater? There are many different types of plant diseases, but here are some common wet weather diseases and what you can do about it.
Powdery Mildew
Powdery mildew is caused by a fungus. It appears as a whitish powder on the surface of leaves. The disease is normally not harmful, although it is unsightly. At first sight, you can apply a fungicide.
Root Rot
Did you know that root rot is actually caused by a fungus and not poorly drained soil? Of course, poorly drained soil is certainly a contributing factor to fungal growth. The fungus which causes root rot can live in the soil and is often spread by flowing water. Leaves will look drought stressed, often turning color as they wilt. If soil has been piled around the crown, remove it carefully to expose root flare. If a replacement plant is needed, consider selecting a plant resistant to Phytophthora root rot.
Blight
Blight can cause sudden browning, yellowing or withering. When a fungus or bacteria attacks a plant’s vascular system, this affects the plant’s water conducting capabilities. Permanent wilting occurs and is often followed by partial or total death of the plant. Infected branches and debris will need to be removed. Consider removing the plant altogether.
Prevention & Treatment Tips
Here are some tips for combating common wet weather diseases:
- Remove leaf debris from the base of the plant
- Properly space your plants
- If needed, thin out branches to improve airflow
- Consider installing drip irrigation lines in landscape beds
- Avoid use of overhead sprinklers, and water at the base of the plant when possible
- Apply fungicide only as directed on the label
- If replacing an infected plant with another in the same spot, consider a variety with disease resistant properties
- Always disinfect garden tools after working with diseased plants
- In some cases, fertilizer can feed certain fungi. Hold off on fertilizing until the disease is controlled.
Don’t forget, we are here for you! If you are having trouble combating wet weather diseases our associates can help you identify the problem and recommend the best course of action. (Pictures are always helpful to us when trying to diagnose the problem.)
