Fight cabbage white butterfly: what to do? 7 home remedies for cabbage worms

The cabbage white is one of the most widespread butterflies and a vegetable pest that should not be underestimated. Almost all types of cabbage serve as host plants for their caterpillars. Here they can cause great damage in a very short time. This in turn can result in enormous crop failures. This makes it all the more important to start fighting at the first sign and to prevent a new infestation.

Recognize the cabbage white butterfly

Damage from the cabbage white from the white butterfly family can occur in the period from May to August. The whitish-yellow, large cabbage white (Pieris brassicae) lays its eggs in clutches of up to 20 pieces. The caterpillars that hatch from this are up to five centimeters long, are mottled yellow-green and black. In contrast, the somewhat yellowish, small cabbage white (Pieris rapae) lays its eggs individually. Its caterpillars are light green and about 3.5 cm long. The best protection against this pest is a bow. If it is already too late for that, you should become active at the latest when the white moths are buzzing through the garden, because then it usually doesn't take long before the cabbage plants are swarming with caterpillars and the first feeding damage is visible become.

Images of damage in the event of an infestation

The large cabbage white lays its eggs on the undersides of the leaves of wild cruciferous plants, which the caterpillars then feed on for 3-4 weeks before finally pupating. Of particular importance are the second generation moths, which lay their eggs under the leaves of cabbage plants or nasturtiums and cause the typical feeding damage there. In contrast, the spectrum of host plants for the small cabbage white is much larger. In addition to cabbage plants and other cruciferous plants, these also include caper, nasturtium and foxtail plants. The caterpillars of the small cabbage white are not only limited to the leaves, but sometimes eat their way into the heart of the cabbage plants. The greatest damage usually occurs in July. If it is too late for preventive measures, it is essential to start fighting as early as possible, i.e. as soon as the first signs of an infestation appear.

home remedies to combat it

Fighting with home remedies can be particularly promising if the caterpillars of this pest have not yet eaten their way through to the inside of the plants. If they do, you can usually only dispose of the affected vegetable plants.

collect

The easiest method is certainly collecting the caterpillars. However, this only works in the case of an initial infestation or occasional occurrence of pests and before the cabbage hearts have formed. The longer you let the caterpillars do their thing, the greater the feeding damage. You should look out for the eggs of this moth from around June/July, which are usually laid under the leaves and then continuously for the hatched caterpillars. The eggs are easy to crush with your fingers. With gloves it's not quite as uncomfortable. Or you brush them off with a hand brush and dustpan.

Tobacco Ash and Stone Powder

If it is not enough to collect the caterpillars, you can try to drive them away with tobacco ash or stone dust or keep away. To do this, first moisten the plants with a watering can or garden hose so that the ash sticks to them. Then they are dusted with tobacco ash. As an alternative to tobacco ash, you can also spread a wafer-thin layer of stone dust over the plants.

Vegetable broths made from tansy and wormwood

Another, very gentle way of fighting the cabbage white and its caterpillars is to use plant broths made from tansy and wormwood. The intense odors of both plants and the bitter substances of the tansy are particularly effective against the cabbage white.

• Blossoms, leaves and stems are used
• Best time for collecting is from July to August
• Suitable for making a broth, fresh and dried herb
• You need 300-500 g fresh or 30 g dried herb and 10 liters of water
• First, soak the herb in water for about 24 hours
• Preferably use rainwater
• Then the whole thing approx. Cook for 20-30 minutes
• Bitter substances and essential oils can thus be released from the plants
• Then let the mixture cool down
• After cooling, pour through a sieve
• Apply the ready-made tansy broth during the cabbage white butterfly’s flight season
• Undiluted on the soil around the plants, and spray the root collars

In June and July, wormwood broth is sprayed directly onto the cabbage plants and the soil in a ratio of 1:3 (1 part wormwood broth to 3 parts water). Anyone who wants to grow wormwood in their garden for the purpose of pest control should do so because of the unfavorable influence on neighboring plants but also for earthworms and other beneficial insects, always in a separate, secluded place in the garden do. For the same reason, wormwood should not be disposed of in the compost.

Cold water extracts from tomato leaves

A cold water extract made from the stinging shoots (sterile side shoots) of tomatoes can be used to control the cabbage white butterfly or cabbage white. its expulsion are used. Here, too, the effect is based on the strong smell, which confuses or scares the pests. should deter.

• Prepare a cold water extract from fresh plant material
• To do this, soak about 1 kg of fresh tomato leaves or scallions in 10 liters of water
• Leave it for 1-2 days
• Then strain and store in sealable containers
• Mixture should not ferment under any circumstances
• Use the finished, undiluted brew shortly before and during the flight time
• Spray plants preferably in overcast weather

As an alternative to a cold water extract from tomato leaves, you can simply spread the leaves and/or shoots of tomatoes on the ground under the cabbage plants. However, new ones have to be refilled at regular intervals. The dried parts of the plant can safely remain on the ground, and thus serve as mulch and nutrient supplier.

Natural predators

Like most pests, the cabbage white has natural predators that can be used to fight both the moth itself and its caterpillars. In addition to birds, there is a certain type of parasitic wasp, the so-called cabbage white parasitic wasp.

• Cabbage white parasitic wasp is actually a braconid wasp (Cotesia glomerata)
• Braconid wasps are only 0.3 cm long
• The first three larval stages parasitize various caterpillars
• Including those of the large cabbage white
• Female braconids lay up to 150 eggs per caterpillar
• The larvae develop inside the cabbage white caterpillars
• Break through the skin of their host caterpillars just before pupating
• This will kill the cabbage white caterpillars

In addition to the use of brackish wasps, you can use an insect hotel to keep other useful insects in the garden lure your home garden and thus not only cabbage plants but also many other useful and ornamental plants from pests protection. In addition to supporting pest control, an insect hotel can attract important helpers for pollinating vegetable, fruit and berry trees. In addition, it is also useful for other predators such as e.g. B. to create suitable shelters for predatory and carabid beetles. These beetles like to use hiding places such as piles of stones, leaves and dead wood, tree stumps, moist areas under ground cover plants or with moss.

Prevent effectively

The best protection against cabbage whites and especially their voracious caterpillars is prevention. The main aim is to prevent the moths from laying their eggs. The best way to do this is with culture protection networks and coordinated mixed cultures.

cultural protection networks

Crop protection nets or corresponding fleeces offer simple, inexpensive and effective protection against a large number of pests, such as e.g. B. the vegetable fly, the cabbage fly, the Colorado potato beetle, the gall midge and various pest butterflies such as the large and small cabbage white. They also offer protection from bird damage.

• Nets used should be fine-meshed (maximum 2 mm) and intact
• Should be deployed early or be stretched over vegetable beds
• Early means immediately after sowing or planting
• Time to apply around April
• Absolutely avoid loopholes for pests
• Dig the edges of the net into the ground all around
• Additionally weigh down with stones

Furthermore, the nets should remain on the beds for the entire cultivation period and care should be taken to ensure that there is sufficient volume, because the cabbage plants grow tall. If very close-meshed nets or even fleece are used, they should be used, especially in summer with large Exposure to heat should be opened and ventilated regularly to prevent overheating of vegetable plants avoid. In order to increase the effectiveness of these nets, crop rotation should be observed at the same time and mixed crops should be cultivated.

comply with crop rotation

Adhering to crop rotation is the basis for healthy, pest-free vegetables and a bountiful harvest. Adhering to crop rotation means that you don't grow the same types of vegetables over and over again in the same location year after year. Otherwise, it increases the risk of pest infestation. For example, cruciferous vegetables such as B. Cauliflower, kale and kohlrabi, can only be grown on the same bed again after four years at the earliest. This also applies to green manure with cruciferous plants, which should also be avoided. Good preceding crops for cabbage are e.g. B. Beans, peas, sweetcorn, celery and rye. The cabbage itself is a rather bad preceding crop.

grow mixed crops

There are many good reasons for mixed cultures. One of them is protection against the cabbage white butterfly or at least a reduction in infestation. Mixed cultures with strong-smelling plants are recommended, particularly to protect against this harmful butterfly and its caterpillars. These include celery, tomatoes, onions, elderberries, broad beans, leeks, borage, lettuce, spinach, marigolds, Privet, nasturtium as well as chamomile, basil, coriander, tansy, mugwort, rosemary, and sage Thyme. The natural defense of these plants against the cabbage white butterfly is based on the mustard oils they contain.

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