Many cucumber varieties grow in the garden, from slicing to pickling, and healthy plants reward you with a bountiful harvest. Unfortunately, cucumber plants often have to contend with bacterial and fungal diseases. We’ll explain the different types of cucumber diseases and ways to treat your plants to keep them productive.
Growing a vegetable garden is satisfying on many levels, and reaping the benefits at the end of the growing season is the reward for all your hard work.
You look forward to harvesting healthy, fresh watermelon, tomatoes, peppers, and cucumbers to fill your pantry and refrigerator with tasty goodness.
Discovering that your veggies are suffering from some type of plant disease is disconcerting, to say the least.
Unfortunately, the problem only worsens if you don’t take care of it immediately. Therefore, it’s vital to know what to look for to prevent losing an entire crop of cucumbers.
- Common Cucumber Diseases and Ways to Prevent Them
- Cucumber Plant Disease Identification
- How to Tell if Your Plants have Cucumber Diseases or Insects
- What are Cucumber Leaf Diseases?
- Diseases that Affect Cucumber Fruits
- How to Treat Cucumber Fungal Disease
- Ways to Get Rid of Cucumber Bacterial Diseases
- How to Manage Cucumber Mosaic Virus
Common Cucumber Diseases and Ways to Prevent Them
A variety of diseases affect cucumbers, and the symptoms range from brown spots and leaf discoloration to wilting and lesions. Learn about the most common cucumber problems and the ways to treat and prevent them from recurring.
Using companion plants for cucumbers like marigolds, beans, and root vegetables help deter insects and reduce the likelihood of unwanted disease.
Cucumber Plant Disease Identification
When planting cucumber seeds, problems that you may encounter are not one of the first thoughts you have. However, cucumbers can be affected by several issues.
Cucumber plant disease identification is not as difficult as you think once you understand the differences between them. Three main types of disease affect plants, and they each have a specific cause.
Identifying Plant Disease
Not all bacteria are harmful, but with the millions that exist, there are roughly 200 types that are harmful to plants and cause bacterial disease.
They are most destructive in warm and humid climates and cause several symptoms, including leaf spot, canker, and soft spot. The bacteria spread through insects, diseased plants and tools, and splashing water.
Fungal diseases are more common than bacterial because thousands of them are harmful to your garden.
These diseases are present in the ground and above ground, causing root rot, leaf spots, mildew, and wilting. Unlike a bacterial disease, fungal spores travel great distances in the air.
The final form of plant disease is viruses. These diseases do not spread by wind or water but rather by insects as they physically enter the virus into the plant.
Sometimes, these viruses infect plants for years before you notice a problem, and the first sign is often yellowing of the foliage.
Disease and insects affect your cukes whether growing cucumbers in containers or the ground. Preventive measures can help.
How to Tell if Your Plants have Cucumber Diseases or Insects
We often think of cucumber leaves turning brown as a sign of disease, but this isn’t always the case. Sometimes an insect infestation causes the same signs as disease, and it’s vital to know the differences to take the right course of action.
Disease vs. Insect
While both insects and disease are a problem for plants that often lead to their destruction if left unchecked, it is important to determine which one is the culprit. Doing this helps you decide which move to take next to save your plant from demise.
The first signs of insects and disease are similar, but there are some variations. If you notice your cucumber leaves turning yellow or brown, inspect both sides of the foliage for bugs and their activity.
Sticky or slimy residue on the leaves and stems are signs of aphids or slugs. Small chewed trails on the leaf surface might be cutworms, and yellow and wilting leaves with holes signify spotted cucumber beetles.
If you do not locate any insect damage during your inspection, your cucumber plants might have a disease.
What are Cucumber Leaf Diseases?
Cucumber leaf diseases affect both new and older leaves, depending on the type, and some of them progress to the fruits if you don’t take steps to remedy the problem. Here are some of the most common leaf diseases and how to tell them apart.
Angular leaf spot is widespread and caused by a bacterium. It begins with small, water-soaked spots on the leave’s undersides that expand, and some cultivars have spots surrounded by a yellow halo.
When the humidity is high, the infected tissue has a milky ooze that dries into a white crust.
Powdery mildew is another common leaf problem for cucumber plants. It is a white, powdery growth that affects the older leaves first, spreading to both the top and bottom of the leaves. It causes the foliage to wither and die prematurely.
Downy mildew starts on the upper surface of leaves, creating yellow spots that later turn brown. It develops rapidly until all of the foliage is brown.
Bacterial wilt affects the vines and leaves of cucumber and muskmelon plants, making them wither and die, and is transmitted by the cucumber beetle. In comparison, fusarium wilt causes the lower leaves to yellow and brown.
Diseases that Affect Cucumber Fruits
Cucumber plant disease identification is essential to growing a healthy garden, and different diseases affect the plant’s leaves and fruits. The disease presents itself on fruits any time between fruit set to harvest and often makes the cucumbers inedible.
Blossom end rot affects cucumber fruits and is one of the most common disorders. A good way to know if a cucumber is bad is to examine the cucumber closely. The bottom end of the fruit where the male or female flower blossomed becomes discolored with blossom end rot, and almost appears rotten.
This area becomes prone to fungal growth after exposure to infection. Fortunately, this problem does not spread from plant to plant and is easy to rectify by adding calcium to the soil.
Anthracnose starts by forming small brown spots on the leaves and eventually progresses to the fruits, where lesions appear on the skin. In comparison, gummy stem blight causes black rot that penetrates the rind and creates irregular spots and wet rot.
How to Treat Cucumber Fungal Disease
Fungus is a common problem that causes cucumber leaf diseases and other plant disorders. While some fungal diseases are treatable with fungicides, others are more problematic, and prevention is the only way to stop them.
Many fungal diseases, such as Alternaria, are treatable with a fungicide, but it’s essential to determine your plant’s disease before using it. These treatments are like pesticides that kill fungus and spores rather than insects.
Fungus thrives in the soil and loves humid, warm conditions. The best way to prevent a fungus from destroying your plants is to use proper watering techniques.
Water your plants in the morning at the base rather than on the leaves. Better yet, install drip irrigation or a soaker hose system to provide water directly to the roots.
Spread mulch over your plants’ soil to stop the dirt from splashing up onto the stems and leaves while you water them or during rainfall.
Ways to Get Rid of Cucumber Bacterial Diseases
There are many causes of bacterial diseases in cucumbers, including insects, and it’s important to take care of the problem right away to keep your garden healthy. Here are common bacterial plant disorders and steps to take to eliminate them.
Many bacterial disease types are not treatable, so the best way to ensure that your plants remain healthy is to purchase pathogen free seeds and bacteria-resistant plants.
Rotate your crops every couple of years and clean up plant debris to prevent spreading disease. These diseases spread from plant to plant, so the best course of action is to remove the affected plants immediately and discard them away from other healthy plants.
The bacteria also infect tools, so it is vital to sterilize them after each use to prevent more infection.
How to Manage Cucumber Mosaic Virus
This plant pathogenic virus is a problem for cucumbers and other cucurbits such as watermelon and sometimes nightshades and leafy greens. It tends to overwinter in biennial and perennial weeds, and preventative actions are necessary to stop its spread.
What is cucumber mosaic virus (CMV)? This virus creates a mosaic design of light and dark green on the leaves and is often spread by aphid feeding. Other signs are flower color breaking, yellow leaf streaks, and ring spots on fruit and leaves.
Since this virus is not treatable, the most crucial step to take for prevention is to purchase virus-free seeds or propagate your own. If this is not possible, there are other ways to manage your garden to keep it free of this disorder.
Use natural insecticides to control aphids and halt insect feeding. Keep your garden weed-free since insects and CMV gravitate toward tall weeds. As soon as you notice symptoms, discard the infected plants and disinfect all of your garden tools.
After you manage cucumber diseases and pests you may wonder about storing your cucumber harvest. Preserving cucumbers without canning them is possible in the freezer but pickles are one of our favorite foods.
Your time and effort are important, and spending days in the garden is an experience that rewards you for your hard work.
Therefore, it’s essential to understand what ails your plants to stop the problem from ruining your crop and prevent it from happening in the future.
There are many cucumber diseases, and knowing what to look for is the first step to prevention, so why not share our cucumber disease guide with the gardeners in your life on Facebook and Pinterest?