Are you a gardener by profession, or are you someone who has recently discovered a passion for gardening? Have you been trying to grow a vegetable garden at your house? If you have started a garden, you might have encountered all kinds of pesky little creatures that might spoil your plants.
Cucumber plants are commonly grown plants in a vegetable garden as they are a part of the staple diet. Did you know that growing them has many health benefits too? But these pesky pests don’t leave the cucumbers, do they?
You might have trouble identifying these pests. If you are wondering about how to prevent and treat them, then don’t fret. Dive into this article now to identify the common cucumber pests, their prevention, and treatment methods.
Table of Contents
Why Grow Cucumbers?
Cucumbers or Cucumis sativus area widely popular plant that is mostly loved by all. These creeping vine plants are often mistaken for a vegetable but are, in fact, a fruit variety.
Cucumber fruits are tasty, crunchy, and comes with a lot of benefits. Moreover, they are good for your skin and have been high in vitamins and minerals. Hence, these have nutritious content in their diet.
There are many cucumber varieties, such as pickled, Gerkin, slicing, burpless, seedless, and many more. These different varieties and their high nutrition make them an excellent vegetable to include in your daily diet.
Cucumbers are known to be highly rich in vitamin K. Also, they have high fiber content and potassium. They also contain many other nutritional contents like Vitamin A, Vitamin C, magnesium, manganese, nitrogen, and calcium.
So, this creeping vine plant is grown in many vegetable gardens. A few of their benefits include:
- They help with the cardiovascular system and thus alleviate your heart condition.
- Has rich antioxidant properties
- It helps in lowering the blood glucose levels and are, therefore, help treat diabetics
- it is known to help people facing obesity as it assists with weight loss
- Excellent at aiding with hydration as it is 99% water, it acts as a detoxifier
- Soothing for your eyes and good for your skin
- Have anti-cancer properties due to rich fiber content
- helps in preventing any bacterial infections
Problems Faced By Cucumber Plants
You might have noticed some of your plant’s leaves rotting or discoloration on plants. There are many diseases and infections that cucumbers face when you are trying to grow them.
However, these occur due to problems faced while growing the cucumbers. The problems could be due to a lot of reasons. It could be due to the harvest time and growth environment of the cucumbers mismatching.
Pests and other insects infection can also contribute to the improper growth of the cucumbers. They can eat the leaves and leaf spots in them. Also, It could be due to the viral, fungal, and bacterial attacks on the leaves that can cause problems and hinder the growth of cucumbers. The plant might end up getting less photosynthesis. The cucumber seeds might not be soaked properly.
Proper insecticide applications would prevent damage caused to the plants. Also, disoriented growth, improper or low yield, and less ripened fruit may be caused due to the different insect populations. Other problems like drip irrigation may cause the leaves always to be dry.
Another thing to note is that the cucumber varieties are prone to deterioration when they are poorly propagated. When insects pollinate these, they are not met with their proper requirements.
Hence, many problems are faced while trying to harvest cucumber fruits, and there is a need to collect them cautiously to collect quality cucumbers. This way, they won’t be susceptible to any infections and would get the tasty and healthy cucumber varieties.
So, there is a need to identify the cause of the problem and treat them for you to get the best kind.
Common Cucumber Pests And Diseases
Pests and diseases among cucumber plants are common and are bigger in number. Why? Because of the inefficient measures are taken to grow them, weather conditions, and the food cycle of the living organisms.
Pests are unwelcomed organisms such as algae, weeds, mosses, and even animals that feed on the cucumber plants and disturb the growth of the turf. They can discolor them or even kill them. Diseases are caused by bacterial or fungal growth in cucumber plants.
So, let’s look at some of the common cucumber pests and diseases that have been the reason for their growth disruption ever since.
1. Cucumber Beetles
Spotted, banded, or striped cucumber beetle is common among cucurbit plants. They commence their feeding as soon as they get to the plant. The striped cucumber beetle attacks the plants through the cracks and reaches the seedling in the soil. Cucumber beetles attack the seedling from beneath and kill the plant at the roots.
Spotted cucumber beetles consist of yellow-green wing covers, eleven black spots, a black thorax, a head, and a yellow abdomen.
Cucumber beetle adults have yellowish-green wing covers and three bright green stripes along with those wing covers. Adult striped beetles are given yellow wing covers, vertical black stripes, a head, and an abdomen.
Cucumber beetles are present throughout the growing season and attack the entire plant, starting from the seedlings to the parts and the flowers and the fruits. They also transmit bacterial wilt. The diseases hubs in the intestine, and this is how they spread from one cucurbits plant to the other.
Some cucumber plants have resistance to bacterial wilts brought by cucumber beetles. The cucumber beetle larvae feed on the plant roots and host in the roots and the stems of the cucumber plants.
The difference between the spotted and striped varieties of the beetles is discussed in detail below.
Spotted Cucumber Beetles
These spotted cucumber beetles belong to the southern parts of North America. These are the spotted variety of the cucumber beetle and hence are charactered by their spots.
These insect pests are also called southern corn rootworms (Diabrotica undecimpunctata howardi) are the small greenish-yellow body that has spots. This cucumber beetle ingests the plants through both their larval as well as adult stages.
The spotted cucumber adult beetles have about six to twelve black spots on their yellow abdomen, distinct from the striped cucumber beetles variety.
Striped Cucumber Beetles
The striped cucumber beetles or Acalymma vittata are characterized by their stripes. These cucumber beetles type contains long strips on their bodies. Cucumber beetleis small yellowish-green beetles that have twelve black stripes in their body.
The difference between the striped and spotted one is that striped cucumber beetles focus on feeding on cucurbits directly. Additionally, the spotted cucumber beetles eat many more other plants.
These can be distinguished from similar-looking pests to western corn rootworm beetle by their ability to damage vine crops. These beetles might also feed on the cucurbit pollen blooms and be separated by their abdomen as the striped beetles have a black abdomen. In contrast, the western corn rootworms have a yellowish-green abdomen.
2. Squash Bugs
Squash bugs are another common pest problem among the cucumber plants and other plants of the home vegetable garden. They start feeding on the saplings and slowly proceed toward damaging the entire cucurbits plants.
The leaves of the cucurbits plants may wilt rapidly, which are signs of the attack of the squash bugs. The leaves become brittle and wither soon with the effects of the squash bug bites.
The adult squash bug looks brownish-black in its appearance and has a flat back. It is merely 1.6 cm long. Their young ones are known as nymphs and have variable sizes that resemble spiders.
Squash bugs appear throughout the growing season, but especially during the spring season. They mate and lay their egg clusters on the leaves of the cucumber plants. Only one generational bug develops each year until the next spring.
3. Squash Vine Borers
Squash vine borers are one of the most serious pest attacks on the gourd family. There are variations in which these borers can cause harm to the home veggie plants, along with the cucumber plants.
The damage is particularly caused by the larvae of the squash vine borers, which affect the plants by tunneling into the stems of the plants. This tunneling kills the plants, more so when the larvae feed into the vines’ basal portions.
Even the fruits and flowers of the plants are susceptible to the effects of the squash vine borer effects. The insect waste and vine wilting occur from the holes in the stems of the cucurbit plants. So, next time you see the wholes in the stems, you know that it’s under the risk of squash vine borer.
The squash vine borer insects occur in the soil in the form of larva in a cocoon. When the moths hatch, the larva bores into vines and slowly crawl into the soil to spin the cocoon. To steer clear of these pests, you’ll further read the treatment and prevention measures in this blog.
4. Alternaria Leaf Blight
Alternaria Leaf Blight is one of the diseases prevalent among cucumber plants. It is caused by a fungus called Alternaria cucumerina. As the name suggests, it is evident from its formations on the leaves of the veggies of the gourd family, and cucumber is one of them.
You will get the hint of their occurrence by noticing the irregular brown spots on the leaves. It can also occur with yellow edges on the leaves of the vegetable plants. They mainly target mature leaves. The brown spots tend to grow into irregular shapes with tints of yellow at the edges.
Gradually, the fungal diseases wilt the leaves, and the plant dies, leaving the fruits exposed to the sun’s direct heat that scalds them. Alternaria leaf blight is common among melons. However, they can also affect cucumber plants significantly.
The wind or the contaminated soil or water carry the fungal spores. Amidst the wet and warm weather conditions, the disease blooms. It survives in the plant debris and returns to affect the plants again in the spring season.
5. Bacterial Wilt
Bacterial wilt is mainly common among the entire gourd family due to their leafy and watery content in their fruits. The disease is caused by the bacteria called erwinia tracheiphila. This bacterial wilt is spread by cucumber beetles mostly. As you may have already come across that diseases are where the pests at.
The formation of this disease is evident from the yellow and dry patches of the wilting leaves of the cucurbit plants. You will notice that in a period of a few days, the stems and vines of the plants start wilting as well, as they turn yellowish and brown.
To ensure that the changes are due to the formation of bacteria is to cut a part of the affected stem and place it in the water. If you see a milky sapling emerging from the stem cut out, you can conclude that it is due to bacterial wilt.
The cucumber beetle transfers the bacterial wilt from the plant they start feeding on and takes them to the other plants where they target feeding on next. The bacteria stay on the whole winter by harboring themselves in the guts of the cucumber beetles.
6. Cucumber Mosaic
The cucumber mosaic is a cucumber disease caused due to the cucumber mosaic virus. By its name itself, you can make out that it is most prevalent among cucurbits plants. The characteristic sign of the occurrence of the viral disease is patterns or spots or lines on the leaves and fruits.
The color of the patterns and spots may be white, yellow, or light to dark green. The veins present on the leaves of the cucumber plants also turn out to be distinctly yellow in color. The plants stop producing fruits, or when they do, they might be small and malformed, along with the leaves.
The symptoms of viral diseases among these plants are not always noticeable. However, higher temperatures, insect predations, undernourishment are some of the stressors that might trigger the symptoms.
The mosaic virus among the cucurbits plants may vary according to the fruit they specialize in. The virus tends to spread via the aphids that feed on these plants and then carry on the grafting of the infected plant to another healthy plant. This transfer takes place through unsanitary tools, boots, and gloves.
7. Downy Mildew
The disease is common in cucurbit fruits and is characterized by their pale green, yellow, or brown spots witnessed in the leaves. Hence, they simply affect the plant leaves and restrict the amount of photosynthesis produced by the plant.
Also, this causes lower plant yield and stunted growth and can be seen mostly in wet or moist areas. The causative organism for downy mildews is Pseudoperonospora cubensis which is an Oocyte, pseudo fungi. This organism can get fastly transmitted to the cucumber fruit through air, wind, or water.
The symptoms of this infection include angular lesions in the veins of the leaves, and these then become water-soaked. The early symptoms to detect is when you might start noticing a bit 0f pale green lesions. The leaf spot on the leaves starts slowing paling out to brown till the plant cells die.
So, it ends up looking like the entire plant is burnt. Also, sometimes this is accompanied by the cucumber fruit leaf experiencing curling. They cause mold formation in the plant.
Downy mildew can be commonly noticed in humid conditions. The cucumber leaves become water-soaked and moist. During rainfall or while irrigation, you might notice the cucumber plant leaves might become easily wet but would essentially go away as dryness comes. This can lead to the formation of a purplish-gray layer behind the cucumber leaf.
However, in the case of downy mildew or even other mildew infections like powdery mildew, it seems the frost in the leaf remains, and this leads to multiple leaf spots. These spots in the cucumber are caused due to the harsh weather conditions in the United States.
Moreover, the oospores or sporangiospores can be identified by the sporocyte cycle of the pathogen. If there is a severe infection, the cucumber leaves show sporulation on the upper layer of the leaves. When you further inspect these under the microscope, a type of fuzzy growth can be observed.
Choosing proper shadings and protection for the plants would help any mildew from forming. These usually infect during 41-86° F, and if it gets too severe, the temperature 59-68° F causes damage to the plants. The pathogen essentially depends on the moisture provided to them to propagate.
These tiny pesky insects can grow on any plant or tree and usually transfer from one plant to another. When they are less in number, it might not cause a direct problem but would lead to cucumber mosaic virus.
They can also lessen the yield production of the fruit and decrease the quality of the cucumbers and make the development of the plant difficult.
Aphids or Aphis gossypii are small in size and are about 1.5 to 3 mm in size. They are also called melon aphid, as they usually gravitate towards melons, watermelons, and cucumbers.
Melon Aphid is made to have a short body with a long mouth. They are quick to propagate and multiply really fast.
The insects come in many different colors like green, brown, and black. Melon aphids suck the cucumber plant with their long slender mouths by piercing the stem or the leaf. Also, the insect has two thin antennas present in their head and have two tubes coming out of their abdomen.
Usually, these insects would gather around areas that are windy in your garden. Melon Aphids, however, aren’t present when there are other insects like ladybugs and lacewing flies. Also, insecticide applications like alpha-cypermethrin can help keep the melon aphid at bay.
9. Cabbage Looper
An insect found mostly in the cabbage family, the cabbage looper (Trichoplusia ni), causes heavy damage to the cucumber plant material. These loopers can be commonly found in the United States and near Mexico. They are a type of brown moths which has distinctive wings. There is a V-shaped silvery noticeable spot on their wings.
They lay their eggs under the surface of their leaves of the cucumber fruit, and the larvae or eggs are rounded and curved with ridges. These eggs are laid separately in a single manner rather than a cluster. The insect pests also have normally smooth skin and long bristle-like structures on their back.
Their larval stage does more harm to the plant as the insects eat three times more of the plant material compared to their normal amount during this stage. Loopers are also called inchworms as they curl or double up for every inch they move.
In the caterpillar stage, these are green and small. These worms do not contain any legs and are usually about one inch long. Many narrow lanes can be detected on the back, which looks striped.
Sometimes these eat and end up making large holes in the leaves. Loopers are difficult to get rid of after they’ve entrenched themselves.
Even though you can get rid of them by discharging some of their natural enemies like parasitic wasps in nature with them else, you can get rid of them by handpicking and throwing them out.
Also, you can control them by using the organic bacterial toxin Bacillus thuringiensis as an insecticide on the larvae of the insect pests.
10. Spider Mites
The cucumber fruit is also susceptible to get damaged by the Acari family member, spider mites. The spider mite drinks the sucks the plant sap of the cucumber plant materials. It also is one of the root causes for the cucumber plant getting infected, and it also lowers the photosynthesis needed for the plant to survive.
These spider mites are present in the underside part of the leaves and settle, spinning their web there. They are responsible for causing grey mold disputes and makes the cucumber fruit dry out faster. It also affects all parts of the plant body, from stems, leaves, and stalks.
Spider mites only plant about 100 to 200 eggs in cucumbers. They have the power to damage the crop within one to two weeks completely. These mites typically develop during dry weather conditions. Also, they can travel many miles both horizontally and vertically when they are waiting out the winter season.
An infected plant can be spotted by yellowish or silvery speckles on its leaves. This greatly affects the fruit’s growth as the insects make the leaves withered or turned yellow, slow down and die.
The spider mites can be washed away by infusing alcohol into them or adding insecticides and pesticides. Detecting the spider mites can be quite the task as they need to detect in their earlier stages.
The treatment methods to cure the pests and diseases of the cucumber plants differ depending upon the type of pests and diseases you are dealing with. For instance, you can use pesticides and insecticides for dealing with insects, algae, and bacteria. On the contrary, you might have to go the extra mile to save your plants from diseases.
1. Controlling Cucurbit Pests And Insects
You can use natural and conventional insecticides to control the terror of the common cucumber pests and also for squash and melon pests. Nevertheless, you should limit the usage of contact insecticides, such as malathion, bifenthrin, or cyhalothrin permethrin, which may kill beneficial predators or parasites.
Make use of less toxic and more natural pesticides that harm the dangerous ones while sparing the beneficial parasites and pests.
Some brands and products that can be used for natural and contact insecticides are also usable to treat cucumber pests. They are good for maintaining the pre-harvest interval (PHI) for insecticides. The PHI is the interval between the harvest and the insecticide application.
In the case of aphids, insecticidal soap sprays work well to control them. You can also spray neem oil extract if the number of aphids and other such pests are larger. Cucumber beetles and squash beetles or squash bugs are also effectively controllable with the use of spinosad.
You can also use the neem oil extract to get rid of vine borers and spray in the evening on the plants to deduce the impacts of the pollinating insects. For cucumber beetles, squash beetles, squash bugs, vine borers, and pickle worms, use bifenthrin, cyhalothrin, or cypermethrin to control them.
However, you should wait 3-7 days after spraying the extract before the harvest to see the results and save the plants from any damage.
2. Controlling Fungal Diseases
Fungicides are the only and the ultimate solution to treating fungal Infections. You can take up any brand available at the local nursery. However, it is to be noted that fungicides make the fruits inedible.
Alternatively, you can use homemade fungicides, a combination of soapy water, baking soda, and vinegar. Some organic gardeners prefer copper fungicides. This way, you can cut the parts of the plant affected by the fungus and prevent it from spreading further.
However, in case of a severe fungal infection of the plant, you may have to get rid of the entire plant, treat the soil, or replace the soil to start afresh.
3. Controlling Bacterial Diseases
Unfortunately, there are no dedicated treatments to cure bacterial infections that affect cucumber plants. However, you can try the other methods enlisted in this blog to take a chance.
Nevertheless, it is always best to remove the whole plant if the bacteria has spread throughout the plant. Prevention works better cure. It is recommended to use only sanitary cultural practices and not expose the stems, leaves, and fruit to water and soil contact.
You must have heard the old saying that goes Prevention is better than cure. Whoever said it was right. When you arrange the correct environment for your plants, or cucumber plants as you may, there are fewer or no chances for the growth of pests and diseases.
Preventing cucumber diseases and pests means understanding the conditions possible in your home garden. Now, it is important to know that the approach toward all kinds of pest prevention varies according to the depth of their impact.
For instance, pests and insects are common among cucumber infections. These are easily preventable using physical barriers, insecticides, companion planting, and beneficial insects.
In case of bacterial infections, organisms affect the plant through their leaves and fruits. Here, you can treat the vines to keep the pests away.
For fungal infections that occur through airborne spores, pay attention to the patterns of the watering habits, pests, and then comes the option of fungicides.
One of the most common and effective ways of pest prevention is the use of virus-free seeds that have been bred for resistance. Seeds and seedlings are usually resilient towards infections. Some disease like cucumber mosaic does not have special prevention or treatment options. So, you need to be wise in making your decisions.
Before the growing season enters, make sure to remove all the plant matter, which includes the leaves, vines, roots, and stems. Moreover, crop rotation is beneficial and should be implemented every year to prevent soil-borne diseases and pests, such as nematodes, beetles, etc.
Here are some go-to tips to help you get started with your preventive measures:
- Always remove infected plants and materials away from the healthy ones.
- Sanitize all the gardening tools, boots, and gloves regularly.
- Check your seeds for probabilities of viruses before planting them.
- Plants are prone to infection through grafting. Thus, avoid grafting.
- Remove aphids and beetles the moment you spot them.
- Spray carbaryl and methoxychlor inclusive insecticides to control pests.
- Use homemade fungicides to kill aphids.
- Remove weeds and plant debris.
- Sanitize the pots and bleach them before reuse.
- Buy seeds only from reputed dealers.
- Soil solarizing is vital before planting the seeds.
- Grow companion plants.
- Try to irrigate underground.
- It is always best to create a barrier between the fruit and the soil with the help of plastic mulch.
- Implement crop rotation, at least in a3-yearly-basis.
Common cucumber pests are prevalent in the garden if the correct measures are not taken. However, it is in your hands to do the right thing about it. You have just come across a list of treatment and prevention measures that help control and prevent the growth of cucumber pests and diseases.
Consider using fungicides and pruning to prevent the spread of diseases. Applying pesticides and home remedies helps control and reduce the occurrence of pests and diseases. Preventive measures like companion planting, controlling irrigation, and sanitization of cultural practices are essential.
You should also be aware of the water amounts and their location. Avoid adding heavy moisture to the soil as it would make the soil soggy. You can use watering cones, soaker hoses, or thin irrigation tubes to water the cucumber plants.
Avoid making a gateway for a breach in the plants’ surface. You do this by avoiding handling the plant excessively. Remember, prevention is always better than treatments.
James Fields is the founder of Gardener to Farmer. His passion for gardening goes back to his childhood days when he would visit his grandfather during the holidays and help him with the plants in the backyard. This has now translated to creating a dependable resource for gardening.