Some of the most common plant diseases to watch out for

A plant disease takes place when an organism infects a plant and disrupts its normal growth habits. Symptoms can range from slight discoloration to death. Diseases have many causes including fungi, bacteria, viruses, and nematodes. Below are 10 of the most common diseases affecting ornamental trees and shrubs:


Blight is easily recognizeable by the suddent death of all plant tissue including leaves, stems and flowers. Blight is typically casued by wet and humid conditions.

2. Canker:

Canker is identifiable by a dead area on the stem that is often discolored.

3. Gall:

Leaf gall is a swelling that occurs on plants. Galls will form on roots, stems and branches and are caused by root knot nematodes and insects.

4. Leaf Curl:

Leaf curl is when leaves begin to curl and wilt. This is caused by several viruses.

5. Leaf Spot:

Leaf spots are yellor or bown lesions (often look like burn marks) that take place on leaves. These are caused by pathogens, fungi, pesticide damage and insect feeding.

6. Powdery Mildew:

Mildew is one of the least harmful diseases that occurs on plants. It is easy to identify by a grey or white powdery coating on the plant. It i caused by fungal pathogens.

7. Root Rot:

Rot is when plant tissues begin to rot away. They become thin and weak, they appear wet or dry and the plant begins to decompose. Rot is caused by pathogens and fungi.

8. Wilt:

Wilt is when leaves start to drop down and the plant begins to appear lifeless.  Wilt is usually caused by over or under watering or by pathogens.

9. Stunting:

Stunting is when plants do not grow to normal size. This is caused by a lack of nutrients, pathogens or damage to the roots.

10. Chlorosis (discoloration):

Chlorosis is when a green tissue turns yellow. It has many causes including pathogens, lack of nutrients, and lack of water.

Unfortunately, there are many diseases out there that can impact the color and vigor of our plants. In some cases they can even infect our entire gardens and cause our precious plants to die completely. Knowing the symptoms of plant disease can help us identify problems early and help us protect our landscapes. If you suspect that you have a disease in one of your plants it is best to call a professional to inspect it. Sometimes it can be a very simple solution, but if left unchecked it can impact some of your other plants.