Despite coming to hate bugs, I am even more worried about the diseases that insects transmit to plants like bacterial blight, as they munch and crunch through leaves.
Illnesses have a whole new dynamic from insects. Disease cannot be seen in the way bugs can. It can move in an unnoticed fashion to cause devastation to an entire crop.
It is also possible to spread diseases to your garden through poor sanitation practices and carelessness without even realizing it.
An infection can occur at any point in a plant’s life cycle. Bacterial blight is either triggered by an injury to a plant or strikes on its own – and once it strikes, it’s game over for your plants.
What is Bacterial Blight?
The bacterium that causes bacterial blight in gardens, Pseudomonas syringae pv. syringae, damages many plants, including several Asian lilac varieties and some large fruit and nut trees.
Ralstonia slanacearum, the bacterium that causes bacterial wilt, is also known as the Southern bacterial blight.
The fungus Alternaria tomatophila and Alternaria solani, however, causes the disease known as early blight. It commonly affects tomato plants. A fungal pathogen is also responsible for late blight, which survives in soil or on diseased plants for a long time. It is also the same as its bacterial counterparts.
These three organisms are difficult to eliminate once established in soil.
There are several types of blight, caused by different bacteria and fungi. This term is often used to describe many different plant diseases caused by dark spots and lesions. Blights of all kinds are challenging to treat effectively.
How Does Bacterial Blight Spread?
As a result, the bacterium can survive easily on plants and in soil. Insects spread the disease, while improper sanitation of garden tools is also a contributing factor. A common place where the bacterium is also found is on plants. However, it does not affect them until it penetrates through an opening in the plant (usually due to insect damage).
Infested with bacteria, bacterial blight substantially reduces a plant’s ability to obtain water and nutrients. If left untreated, it will ultimately cause death. It is more likely that certain types of blight will cause problems in humid, hot weather.
Signs of Bacterial Blight
The most obvious symptom of the disease is necrotic tissue on the leaves. Dark brown spots with yellow rings are another sign of bacterial blight. This disease causes plant foliage to die back, as well as blackened twigs and branches. Eventually, the disease causes plant foliage to turn brown.
If sap is oozing from the wound of trees or other woody plants, the presence of bacterial blight is evident.
Any plant that is endangered should be identified early if it is to be saved. For plants that have been infected by fungal blight, I would suggest that you get rid of affected plant material as soon as possible to avoid spreading the disease to the rest of the crop.
Which Plants Are Vulnerable?
Although many plants are susceptible to bacterial blight, plants that have insect damage are far more likely to contract the disease than those without an infestation. It is because insect feeding on plant foliage allows bacteria to enter through cracks and openings for the bacterium to spread to other parts of the plant.
Other types of blight are more likely to affect edible garden plants, such as tomatoes and potatoes. Bacterial blight occurs more often on woody plants such as trees and shrubs.
How to Prevent Bacterial Blight
It’s best to cultivate a healthy environment for your plants to prevent their exposure to this disease. It is important that plants have room to breathe and are watered from below to prevent moisture buildup on foliage. Make sure all your gardening tools are properly cleaned throughout the season too.
You should rotate your crops every three years to prevent pathogenic diseases from attacking susceptible plants.
Choosing disease-free plants for your garden or starting seeds will prevent introducing blights to your environment. Be sure to choose disease-resistant varieties as well.
Annual soil testing can prevent an imbalance of nutrients that could exacerbate the disease.
You can mulch around plant bases to prevent splattering water from spreading soil-borne pathogens to foliage.
As a preventative measure for fungal blight, spray plants before symptoms appear with fungicide before the disease even manifests itself.
How to Treat Bacterial Blight
Even after a plant becomes infected, it is possible to salvage healthy parts and keep it alive, but bacterial blight cannot be treated. Treatment for bacterial blight is only management. It does not actually get better.
As part of controlling the disease, it is important to dispose of infected plant material. Don’t compost it. Remove the damaged leaves and stems and throw them away.
Ensure that pruning tools are sanitized and clean after use to prevent spreading disease to other plants.
In some cases, disease can continue to progress after pruning. In these cases, it may be best to cut your losses and dispose of the whole plant. Allowing it to remain in this condition may cause the disease to spread to other garden plants.
It is possible to use fungicides where a fungus is involved in severe cases of blight, but they are not as effective if the disease has advanced to an advanced stage. In addition, even fungicides can only reduce the spread of the disease.
Controlling Bacterial Blight in the Soil
It can be very difficult to remove blight once it has taken hold in your gardens soil. Solarization, however, does appear to be a method that can help kill earth-borne pathogens like blight.
Covering your garden soil with a clear plastic sheet harnesses the power of the sun and produces more heat. As the soil heats up, nasty things hiding inside are killed. However, it is a long process, so you must remain patient.
A solarization process can also kill weed seed, but it is not as effective as a pesticide when it comes to airborne pathogens. Solarization takes 6 weeks, and you should do it during the hottest part of the season.
Although solarization removes pathogens and weeds from your soil, it doesn’t offer a permanent solution since they can always end up there again. Solarization also offers benefits from a certain depth.
Deeply rooted perennials are probably not affected by the high heat, but anything with a root system shorter than about 6 inches will still have trouble.
The soil should not be deeply tilled once the process is completed. If you do, you are likely to bring pathogens and weed seeds to the surface.
The Bottom Line
It’s not funny to have bacterial blight in your garden. Once it has taken over, it’s difficult to remove. Prevention is key, but if that doesn’t work, our tips will help you get the garden back on track.