Scroll To Top


What is a plant disease?

Plant disease is any pathological condition caused by other organisms, such as bacteria, fungi, or viruses.

Fungal diseases are the most common while bacterial diseases are relatively rare. Symptoms vary considerably in appearance and severity, but the growth or health of the plant is almost always affected and in severe attacks, the plant may die.

The rate of infection is affected by factors such as weather and growing conditions. IM some cases, the disease causing organism is spread by a carrier, such as an aphid. The pathogen is sometimes visible on the plant as a discolored, distorted or wilting area of the plant.

Lawn Diseases

Sometimes bad things happen even to the healthiest lawns. Lawn Diseases are one of those things. Diseases are enough to perplex all of us to no end. Many lawn diseases are not easy to identify and to distinguish from other problems such as pests or poor maintenance. Ask anyone who has encountered lawn diseases and they will tell you how frustrating they can be. Much like human diseases, lawn diseases can be difficult to properly diagnose and even harder to treat correctly. And, just when you thought you had all of your lawn care problems solved. Fear not, we have some tips to help you identify and treat your lawn problems.

Chances are that some of you reading this will already have a lawn disease problem. If so, the most common controls is to use a fungicide on your lawn. Various types of fungicides exist, so make sure that you use the right one. Some of the broad-spectrum fungicides will not only treat your disease, but can kill-off other good organisms and insects as well—not good! Since most lawn diseases are identified in spots before they spread, it's a good idea when using fungicides to first try to spot treat these areas to minimize the damage a fungicide can cause to your lawn's ecosystem.

As always, follow the instructions listed for each fungicide to help prevent possible damage to the environment and illnesses that can be caused by its use.


The best treatment is prevention. Avoid circumstances that are more likely to allow diseases to infect lawns. Proper watering, mowing regularly and at the correct height (don't mow too short). In some instances, disease is spread by mowers that have recently cut infected lawns. If you hire an outside maintenance service, discuss with them precautions they take to avoid disease spread.

Thatch is also a breeding ground for many diseases. Aerate often if necessary (2 times a year) to reduce thatch to less than 1/2". Improve drainage if water regularly stands after a heavy rain. Be careful of over-watering, or watering at the wrong time of day (see watering info).

Ask a professional lawn care provider for specific treatments recommended for your specific geographic area. (See Selecting a Lawn Pro in your area)


Diseases can form a resistance to fungicides after repeated use. Try to minimize this through using various types of fungicides.

There are three types of fungicides available.

1. CONTACT FUNGICIDES: once applied, remain on the plant's surface and kill spores that come in contact with it.

2. SYSTEMIC FUNGICIDES: applied to the leaves and then moves throughout the plants circulation system including its roots. Has a longer residual life span than contact types.

3. PENETRANT FUNGICIDES: similar to Systemic types, but act as a preventative treatment to stop the growth of pathogens.

Additional information...

  • Keep pesticides in the original containers with the label attached. The label includes instructions for safe storage and usage. Store pesticides where they are out of reach of children and pets. A locked cabinet or area that is ventilated is best.

  • Avoid storage areas that freeze, which might cause products to change physically or chemically, leading to ineffectiveness or even plant injury. Freezing containers are more likely to burst.

  • Pesticide containers should be inspected occasionally for damage or leaking. Leaking containers should be placed in a larger container such as a plastic bucket to prevent more pesticide from contaminating the storage area. Label the new container with the pesticide's name and active ingredients.


  • Only buy strong, vigorous plants that look healthy. Don't purchase plants showing dieback or discolored stems that have leaves with an abnormal color, are wilted or distorted.

  • Purchase plants suitable for your specific climate. Most reputable nurseries only carry suitable plants, however, mail order plants can be purchased from almost any climate and shipped to unsuitable climates. Purchasing plants not suited to specific climates only invite problems.
  • Follow specific label directions for watering practices, light requirements, and fertilization recommendations.

  • Use good garden hygiene. Maintaining a neat and well-managed garden is one of the most important ways to reduce the risk of disease attack. Examine plants regularly so identification of problems can be made as soon as possible. This will reduce the chance of having the infestation spreading.

  • Remove and dispose diseased parts of plants. This may seem like a lot of work, but it will go a long way in controlling plant diseases.

  • Severely infested plants may not be saved. These plants should be removed as soon as possible to prevent further spread of the infection.