Easy Method to Kill Cabbage Worms on Brussel Sprouts, Broccoli & Cabbage

When cabbage worms were destroying his Brussel Sprouts, he used this method to eliminate them.

Cabbage worms are a common and destructive pest that can wreak havoc on your cabbage and broccoli plants in the garden. These small green worms voraciously feed on the foliage of these vegetables, causing significant damage and potentially leading to a complete loss of crops if left unchecked. Addressing the issue of cabbage worms as soon as it arises is vital to ensuring a healthy and productive garden.

There are several methods available to both prevent and control cabbage worms on your cabbage and broccoli plants. Some of these methods are organic and others chemical-based. By inspecting your plants regularly, you can identify an infestation early on and implement effective measures to deal with these pests. This article will discuss various strategies for killing cabbage worms, as well as tips for keeping them off your crops in the future.

Implementing a combination of preventive and reactive measures can help ensure the best possible outcome for your garden. Join us as we explore the different methods to kill cabbage worms and maintain the health and vitality of your cabbage and broccoli plants.

Identifying Cabbage Worms and Their Damage

Cabbage Worm Species

There are three common species of cabbage worms that are known to attack cabbage, broccoli, kale, and other plants in the brassica genus: the imported cabbageworm, cabbage looper, and diamondback moth.

  • Imported Cabbageworm: These caterpillars are the larvae of the cabbage white butterfly. They are velvety green and have a thin yellow stripe along the center of their back.
  • Cabbage Looper: Cabbage loopers are yellow-green caterpillars with no middle legs. As a result, they raise and lower their bodies when moving (similar to an inchworm).
  • Diamondback Moth: The larvae of the diamondback moth are pale green and have a distinctive forked tail.

Signs of Infestation

When cabbage worms infest your cabbage, broccoli, or kale plants, there are several signs that can help you identify their presence. Here are some indicators of an infestation:

  • Physical Presence of Caterpillars: The most obvious sign is the presence of the green larvae or caterpillars on the underside of the plants. Actively search for them, particularly in the case of imported cabbageworms and cabbage loopers.
  • Cabbage White Butterfly Sightings: If you notice white butterflies around your brassica plants, it may indicate the presence of imported cabbageworms.
  • Damage: Cabbage worms can cause significant damage to plants in a short period of time. Look for holes in the leaves, skeletonized leaves, or even entire plants that have been consumed.
  • Droppings: Another sign of infestation is the presence of caterpillar droppings (also known as frass) on the leaves or surrounding soil.

Remember to closely monitor your cabbage, broccoli, and kale plants for these signs of infestation, as early detection is crucial for effective control of cabbage worms.

Cabbage Worm Life Cycle

Eggs

Cabbage worms begin their life cycle as eggs laid by the adult female butterflies, typically the cabbage white (also known as small white butterfly) or the imported cabbageworm. These species lay their eggs on the undersides of cabbage and broccoli leaves. The eggs are small, oval-shaped, and yellowish in color. Depending on the climate, eggs can hatch within a week.

Larvae

Once the eggs hatch, the larvae emerge and begin feeding on the host plant. Cabbage worms are voracious eaters and can quickly cause extensive damage to cabbage, broccoli, and other leafy crops. The larvae stage lasts for two to three weeks, during which they will continuously feast on the foliage. As the larvae mature, they can be easily identified by their green color, resembling the foliage they feed on.

Pupa

After the larvae have completed their growth, they transform into pupae. This stage takes place within a chrysalis attached to a leaf, stem, or other nearby surfaces. The pupation process usually lasts for one to two weeks, depending on the temperature and humidity. The pupa appears as a green or brown capsule-like structure, camouflaging with the surroundings.

Butterflies

Once the pupation stage is complete, adult butterflies emerge from the chrysalis. The small white butterfly has a wingspan of 1.5-2 inches (38-63 mm) and is characterized by its white forewings with black tips. As adults, they primarily feed on nectar from flowers and reproduce, starting a new generation of cabbage worms. Depending on the climate, cabbage worms can have between two to eight generations per year.

Throughout the cabbage worm lifecycle, beneficial insects such as ladybugs, lacewings, and parasitic wasps can help control their populations by preying on eggs, larvae, and pupae stages. Periodic monitoring and implementing natural control methods are critical in managing cabbage worm infestations and protecting your plants.

Organic Control Methods

Handpicking

Handpicking can be an easy and effective way to control cabbage worms on your cabbage and broccoli. This method involves manually removing the worms from the plants when you spot them. Wearing gloves may make it more comfortable for those who are squeamish with handling insects. Regular checks and handpicking can keep the population under control.

Floating Row Covers

Using floating row covers as a barrier can help protect your cabbage and broccoli plants from cabbage worms. These covers prevent the adult worms from laying eggs on the leaves, thus preventing infestation. Make sure to secure the row covers well so that the pests don’t find a way in. This method is most effective when used alongside other control measures.

Beneficial Insects and Predators

Introducing beneficial insects and predators into your garden can help control the cabbage worm population. Some examples include:

  • Ladybugs: They feed on various pests, including cabbage worms.
  • Trichogramma wasps: These tiny parasitic wasps lay their eggs in the eggs of pests like cabbage worms, preventing them from developing further.
  • Paper wasps: These predators feed on caterpillars such as cabbage worms.
  • Spiders: Many spiders are natural predators of pests like cabbage worms.
  • Birds: Encouraging birds to visit your garden can also help reduce the number of pests.

Natural Pesticides

Using natural and organic pesticides is another effective method for controlling cabbage worms on cabbage and broccoli. These pesticides are generally safe to use and do not harm the environment or beneficial insects.

  • Bacillus thuringiensis (BT): A bacteria that can be sprayed or dusted onto the leaves of your plants, as it is lethal to the worms when ingested.
  • Neem oil: Neem oil can be mixed with water and applied as a spray for controlling cabbage worms and other pests.
  • Diatomaceous earth: A powder made from fossilized algae that can be applied to the leaves of your plants, which causes the worms to dry out and die.
  • Spinosad: A naturally occurring bacterial product that can be applied as a spray to control caterpillars, including cabbage worms.
  • Cornmeal: Wet your plants and sprinkle cornmeal on them, causing the worms to eat it and swell up, eventually dying.
  • Flour: Dusting flour on the leaves of your plants can lead to the worms ingesting it and dying from dehydration.

Preventing Future Infestations

Companion Planting

Companion planting is an effective method of preventing cabbage worm infestations in your garden. Planting herbs like thyme, dill, and marigolds can repel cabbage worms and other garden pests. These plants emit strong odors that deter pests from laying eggs on your cabbage and broccoli. Similarly, you can use soapy water to spray on the foliage of your plants, making them unattractive to pests.

Soil Management

Proper soil management plays a crucial role in preventing future infestations of cabbage worms. Rotating crops within the brassica family, including horseradish, turnips, collard greens, kohlrabi, radish, rutabaga, mustard greens, Brussels sprouts, cauliflower, and bok choy, helps to break the life cycle of cabbage worms and other pests. This reduces the likelihood of pest populations building up in your garden.

Introducing natural predators like chickens can also help keep cabbage worm populations in check. Chickens will not only feed on the worms but also help control other pests and improve overall soil health.

Polyculture Farming

Polyculture farming involves growing a mix of different plants in the same area. This diverse ecosystem makes it more challenging for pests like cabbage worms to thrive. By interplanting various crops, you create an environment that is less conducive for the growth and reproduction of cabbage worms and other pests like the inchworm. Additionally, polyculture farming can increase the overall resilience of your garden by fostering a healthy ecosystem that supports beneficial insects and other natural predators.

Applying organic pest control methods, such as Bacillus thuringiensis (Bt) spray and neem oil spray, can effectively control cabbage worms while safeguarding the environment. Bt is a natural soil-dwelling bacterium that is toxic to caterpillars but harmless to humans, pets, and beneficial insects. Neem oil, extracted from neem tree seeds, is another organic pesticide that not only kills cabbage worms but also repels the moths that lay the eggs.

By implementing these preventative techniques, you can keep your cabbage and broccoli plants healthy and free from cabbage worm infestations.