Cucumber beetles are striped and/or spotted insects that harm a variety of crops. On cucurbit plants, such as cucumbers, pumpkins, watermelons, squash, and zucchini, you may find tiny yellow or orange beetles crawling. The yellowish-green cucumber beetles, which are spotted or striped, devour shoots, blossoms, and foliage until they kill your plants. If you want to preserve your harvests, controlling and eliminating cucumber beetles is critical.
Cucumber beetles, which are native to North America, normally begin their harmful behavior in June. Even before the striped or spotted yellow beetles emerge, their larvae can already be damaging crops. On your cucumber plant leaves, you may have seen several yellow beetles with black stripes.
Maybe you’re a little confused about what to do after seeing greenish-yellow insects with huge black dots on their backs. In this case, two pests that torment cucumber plants, the spotted cucumber beetle and the striped cucumber beetle, are identified and eradicated in this article.
What Are Cucumber Beetles?
Cucumber beetles eat cucurbit crops and transmit plant diseases. Plants like cucumbers, squash, eggplants, beans, and melons are all eaten by striped and spotted yellow cucumber beetles. Acalymma vittatum is the scientific name for the striped cucumber beetle, whereas Diabrotica undecimpunctata is the scientific name for the spotted cucumber beetle. The Chrysomelidae family includes both genera.
What Do Cucumber Beetles Look Like?
Adult spotted cucumber beetles have a yellow belly and twelve fairly big black spots, and are 0.25″ (6 mm) long. The yellowish wing covers of striped cucumber beetles are similar, but they have three black stripes running down their backs. Six legs, two antennae, and a black head characterize both beetle species.
Because they spend the majority of their lives underground munching on cucumber roots, cucumber beetle larvae are difficult to see. Before pupating, the cucumber beetle larvae develop up to 0.47 inch (12 mm) long and resemble yellowish-white worms with black heads. Around their heads, they have three sets of brown legs.
Cucumber Beetle Life Cycle
An adult cucumber beetle emerges after 40 to 60 days after the egg is laid. The females lay a tiny oval-shaped yellow egg in mid-spring, which becomes a spotted or striped cucumber beetle. In ideal conditions, eggs take six to nine days to hatch. The root of the host plants, cucumbers and other cucurbit crops, is consumed by the creamy-yellow larvae after they hatch.
Cucumber beetle pupation is the second stage in their life cycle. To begin pupation, the larvae build a tiny chamber in the soil. Little beetles emerge after six to ten days. The yellow beetles’ abdomen is speckled or striped, depending on the species.
Cucumber beetles feed on leaves, stems, and other plant materials when they become adults. When the beetles are adults, they cause the most damage. Cucumber beetle larvae, on the other hand, can cause minor damage to crops.
How to Identify Cucumber Beetle
Because of the spotted or striped patterns on their yellow abdomens, the two species of cucumber beetle are easy to differentiate. The black bands that run down the length of striped cucumber beetles’ yellow backs are three. The back of the spotted cucumber beetles is bright yellow or green, with 12 black markings.
What Do Cucumber Beetles Eat?
The spotted and striped yellow beetles devour cucumber plant leaves, as their name suggests. As a result, beetle damage threatens many cucurbit crops. These beetles consume pumpkin, squash, and watermelon foliage, in addition to cucumbers. Leaves from cotton, legumes, corn, and soybean crops are also eaten by cucumber beetles.
Cucumber Beetle Larvae Damage
During the larval stage in the soil, cucumber beetles begin to feed on plants. The larvae do little harm to the plant’s overall health, despite the fact that yellowish-white grubs feed on roots. Nevertheless, it is difficult to protect crops against cucumber beetle damage since controlling cucumber beetle eggs and larvae is challenging.
Signs of Cucumber Beetle Damage
Cucumber beetle damage may manifest itself in two ways, either through the presence of beetles or holes. Adult cucumber beetles begin by feasting on plant leaves, destroying tiny plants in the process. Second, foliar diseases like Pseudomonas lachrymans, which causes bacterial wilt, are transmitted by cucumber beetles.
The bacterium can easily multiply in the holes of leaves. Cucumber beetles may also harm cucumbers, pumpkins, squash, and melons in a different manner. The mature beetle activity may cause damaged fruit, making it appear unappealing.
When cucumber beetles attack young plants, it causes the most severe plant damage. Adult cucumber beetles can quickly defoliate small cucurbit plants because they are so small. The plant’s vascular system is damaged if bacterial diseases strike, resulting in wilting. Infected plants can quickly spread to other cucumber crops if beetles feed on them.
Spotted cucumber beetle damage to plants
In comparison to their striped counterparts, adult spotted cucumber beetles damage a wider range of plants. Around 200 plant species are susceptible to the pest that destroys plants. In addition, they’re more of a problem in the southern US. Similarly, rather than cucurbit plants, spotted cucumber beetles prefer to lay eggs on maize and grasses.
Striped cucumber beetle damage to plants
Cucurbit plants are commonly attacked by adult striped cucumber beetles, but other species are rarely attacked. You’ll also discover that, rather than just being found in the southern states, yellow and black striped beetles are common across the United States.
Where Do Cucumber Beetles Come From?
Cucumber beetles may be found all around the United States, including cucurbit crops and others. In compost, trash heaps, and agricultural fields, the beetles overwinter. The females will then lay eggs in the soil soon after they emerge from their winter hideaways in mid-spring. Ultimately, in order to commence their harmful activity, a new generation of cucumber beetles emerges from the root of the plants.
How to Get Rid of Cucumber Beetles
It may be difficult to get rid of cucumber beetles. It may be difficult to pick the little yellow and black speckled or striped beetles off of plants. cucumber beetles are difficult to find on crops because they are most active in the late evening and early morning.
Your cucumber, watermelon, pumpkin, or squash plants have reached maturity. Getting rid of the bothersome insects in that scenario is not required. Only immature plants are affected by the beetle damage, and defoliation has no effect on older crops. If you notice striped or spotted cucumber beetles on your cucurbit crops, here are a few things you can try to eliminate them. To ensure you reduce beetle populations as much as possible, employing a multi-faceted approach is often the best option.
Beneficial Insects Kill Cucumber Beetles
Cucumber beetles are eaten by many beneficial insects, which may help you get rid of them from your garden. Tachinid flies, harvestmen, braconid wasps, and soldier beetles are some of the natural enemies of cucumber beetles. Bats and predatory mites are also known to be effective biological control agents, according to some studies.
Nematodes, according to some studies, may be used to kill cucumber beetle larvae before they emerge from the ground and begin devouring your crops. So, in late fall or early spring, nematode-based soil-drenching treatments might help eliminate larvae and avoid cucumber beetle invasion.
Neem Oil Can Kill Immature Cucumber Beetles
In mid to late spring, a home-made neem oil spray may effectively kill immature cucumber beetles. Combine 2 tsp. of neem oil and 1 cup of water in a spray bottle. 1 tsp. of neem oil is recommended. In a spray bottle, mix Castile soap with 1 quart (1 liter) of water. In the evening, shake vigorously and liberally spray on leaves. To get rid of the beetles, simply repeat every seven days.
Since it contains azadirachtin, neem oil can be used to kill insect larvae and immature insects. According to research, neem oil extracts harm egg development, prevent larval growth, and impede feeding.
Use neem oil to kill cucumber beetle larvae
Cucumber beetle larvae that live in the soil may also be controlled with neem oil. You must apply the solution in early spring to use this soil drench method. Use 2 tbsp. of neem oil to make a solution. In every gallon of water, use Neem Oil. Next, use a hose sprayer or watering can to water your lawn. Lastly, in the spring, spray your veggie patch with water to kill cucumber beetle larvae.
Handpick Cucumber Beetles to Eradicate Them
Have you seen a severe infestation of cucumber beetles on your cucurbit crops? You might need to manually remove the bothersome insects if this is the case. Handpicking individual beetles may be too difficult. Several gardeners, on the other hand, have reported successfully capturing large numbers of cucumber beetles with a leaf blower/vacuum.
You should remove the plants as soon as you notice signs of bacterial wilt on them. Bacteria can easily be transmitted from beetle-infested plants to other plants in your yard.
How to Control Cucumber Beetles
Vigilance from early spring is critical for managing beetle populations if cucumber beetles have been a problem in your area. Row covers, mulch or reflectively mulched ground, and kaolin clay application are some effective cucumber beetle control strategies.
Use Row Covers for Cucumber Beetle Control
It’s essential to install floating row covers over cucumber seeds or other cucurbit plants after they’ve been sown. Row covers should be applied as early as possible in June. But, until your plants begin to bloom, this control technique is only effective against cucumber beetles. Since pollination necessitates the removal of the covers, this is a requirement.
Use Mulch to Deter Cucumber Beetles
Another method to keep cucumber beetle populations in check is mulching. Mulching around crops serves many functions, including protecting the plants. First and foremost, it prevents egg-laying and the development of larvae in the soil. Mulch, on the other hand, aids insect predators and boosts soil microorganisms, which helps to promote plant health.
According to some research, reflective aluminum mulch may help reduce the number of cucumber beetles on fields. The mulch also has a deterrent effect on nasty insects like aphids and cucumber beetles, preventing them from feeding on plants. Another advantage of this was that it inhibited bacterial wilt transmission between plants.
Companion Planting Can Help Control Cucumber Beetle Numbers
Companion planting is one of the easiest ways to prevent cucumber beetles from becoming pests. This is a technique of planting cucurbit crops and cucumber beetles together, also known as intercropping. Radish, broccoli, and nasturtium are all plants that act as a cucumber beetle deterrent.
Planting trap crops is another method of using natural beetle control. The aim is to develop a few squash plants that attract a large number of cucumber beetles. You may draw destructive beetles away from your primary crop by using this technique. This, however, may not apply to all tiny gardens.
Kaolin Clay Can Help Control Cucumber Beetles
Natural cucumber beetle repellent kaolin clay may help to manage populations. Cucurbits’ antennae get coated with a sticky layer when they’re sprayed with kaolin clay, making it tough for them to find their way around your property. According to studies, kaolin clay may be used to control cucumber beetles in a variety of ways. Using it in combination with other control methods, however, may help your vegetable patch.
How to Prevent Cucumber Beetles
In order to prevent cucumber beetles from multiplying in your yard, the best method is to eliminate them. Crop rotation and the planting of cucumber beetle-resistant cucurbits cultivars may help reduce the incidence of cucumber beetle damage. Here are a few quick tips for preventing striped and spotted beetles from destroying your crop.
Plant Resistant Varieties of Crops
Cucumber beetles are repelled by certain cultivars of cucumbers, squash, melon, and eggplants. The chemical cucurbitacin, which attracts the beetles, is lower in these crop varieties. These beetle resistant cultivars may force the beetles to travel elsewhere for food.
Crop Rotation Can Help Control Cucumber Beetles
In organic gardening, rotating crops are a proven and effective method of pest reduction. Cucumber beetles tend to overwinter previous year’s crop, which is a problem. As a result, you might try to plant your following year’s crop some distance away from the previous one in order to prevent a beetle invasion. While crop rotation is a useful practice for organic farming without chemicals, it isn’t the only way to keep cucumber beetles at bay.
Planting Later in the Season
When cucumber beetles begin to lay their eggs in mid-to-late May, they are active. As a result, planting cucurbit crops in mid-June may help keep adult beetles at bay. Your crops have a greater possibility of surviving now that the height of beetle consumption has passed.
Other Preventative Methods of Eradicating Cucumber Beetle Damage
Other techniques to minimize cucumber beetle issues in a vegetable garden may be found here:
- During the early leaf stages, be careful with cucurbit plants, since this is when the most damage occurs.
- Because bacterial wilt may impact bigger plants, keep removing beetles until fruiting.
- During the growing season, protect existing cucumber plants from egg laying by applying plenty of mulch.
- Before more beetles can feed on them and spread the bacteria, remove plants that are exhibiting symptoms of bacterial wilt.
- Adults cannot overwinter there if you remove garden debris and leaf litter after the summer.