Pests

Flea Beetles (Cruciferous Flea Beetles)

This is perhaps the most dangerous and widespread pest of all cabbage seedling crops. Cruciferous flea beetles are small (1.8–3.5 mm) jumping beetles that are active in hot, dry weather. There are several species (wavy, pale‑legged, southern, black), but they cause similar damage.

How to recognise damage?

Flea beetles gnaw small pits and ulcers in the leaves, leaving characteristic "dotted" damage (Akhatov et al., 2013). During mass outbreaks, they can completely skeletonise a leaf, leaving only a network of veins, often leading to the death of young plants. They are especially dangerous for seedlings and recently transplanted plants because they can destroy the growing point, and the plant will die.

Why is a quick reaction so important?

Flea beetles are very voracious and mobile. Under favourable hot weather, they can destroy plantings within 1‑2 days (Akhatov et al., 2013). Delaying treatment can cost the entire crop.

Gardener’s tip: Regularly inspect seedlings, especially on sunny days. The first signs are small light spots or holes on the leaves. Treatment should begin immediately upon detection.

Cabbage Fly

Unlike flea beetles, which feed on the above‑ground parts, the cabbage fly is a subterranean pest. The emergence of flies in spring (in the temperate zone – in the second half of May) coincides with transplanting seedlings into the ground (Starcev, 2021). The pest is widespread, especially dangerous in the Non‑Black Earth region and Siberia.

How to recognise damage?

The fly lays eggs on the root collar or on the soil near the stem. The hatched white legless larvae bore into the roots and stem, tunnelling through them. Externally, this manifests as wilting of plants even with adequate watering, they lag in growth, and with severe infestation they die (Starcev, 2021). Plants are easily pulled out of the ground because the roots are rotten or chewed off.

Why does this happen?

The damaged root system cannot supply the plant with water and nutrients. This happens especially quickly in dry, hot weather when moisture is already scarce and the plant cannot compensate for the loss of roots (Akhatov et al., 2013).

Gardener’s tip: Carefully inspect the root collar when transplanting seedlings. If you find eggs (small, white, cigar‑shaped) or signs of damage, take measures. Hilling up damaged plants can help them grow additional adventitious roots and survive.

Caterpillars of Cutworms and Whites

Young caterpillars, especially those of moths (cabbage cutworm) and whites (large cabbage white, small white), also cause serious damage to seedlings. The first generations of these pests appear in late spring – early summer.

How to recognise damage?

Young caterpillars of the early instars first scrape the parenchyma (flesh) from the underside of the leaf, leaving "windows" (Akhatov et al., 2013). As they grow, they begin to eat the leaves from the edges, and cutworm caterpillars may bore into stems and stalks, causing the plant to die. The presence of faeces is another sure sign of their presence.

Why is this important?

At the seedling stage, even minor damage to the leaf apparatus severely weakens the plant. Leaves are the "factory" for producing nutrients. Damage to the growing point by cutworm caterpillars can stop development and lead to the formation of ugly, unmarketable small heads.

Gardener’s tip: Regularly, especially in the evening, inspect the underside of leaves. There you can find egg clusters of whites (yellow heaps) and young caterpillars. Manual collection of eggs and caterpillars on a small area can be very effective.

Slugs

Naked slugs are nocturnal pests that are especially active in rainy and cloudy weather. They damage not only cabbage but also many other crops (Starcev, 2021).

How to recognise damage?

Slugs gnaw irregularly shaped holes in leaves and stems. The main distinguishing feature is the presence of shiny, silvery, dried slime trails on plants and soil (Akhatov et al., 2013).

Why is this dangerous?

Slugs can completely destroy seedlings and young plants in one or two nights. They prefer moist, shaded areas with dense vegetation and easily penetrate under covers.

Gardener’s tip: Create unfavourable conditions for slugs: avoid dense plantings, remove weeds, do not over‑moisten the soil. Traps are effective – pieces of boards, slate placed on wet soil. Under them, slugs gather during the day, and they can be easily collected and destroyed.

Cabbage White (Large Cabbage White)

This is perhaps the most famous and conspicuous pest. Large white butterflies with black spots on their wings fly during the day and lay eggs on the underside of leaves in clusters of 15–200 (Akhatov et al., 2013).

How to recognise damage?

Young caterpillars first scrape the flesh from the underside of the leaf, leaving the upper skin intact – characteristic "windows" form. As they grow, they spread over the plant and begin to roughly eat the leaves from the edges. During a mass outbreak, only thick veins may remain of the leaves (Starcev, 2021). The caterpillars are yellow‑green with black dots and yellow stripes on the sides, up to 40 mm long. They are quite visible.

Why is this dangerous?

The caterpillars are extremely voracious. An adult can destroy a significant part of the leaf surface in a few days. In addition, they contaminate the leaves and heads with their excrement, reducing the quality of the crop.

Gardener’s tip: Regularly inspect the underside of leaves and destroy egg clusters and young caterpillars while they are still together. Use floating row covers ("Agrospan", "Agrotex") to protect against butterflies. This is the simplest and most environmentally friendly way to avoid the problem.

Diamondback Moth

This small pest (wingspan up to 15 mm) is inconspicuous in appearance but can cause enormous damage. The moths fly at dusk and lay eggs on the underside of leaves. In warm regions, it can produce up to 3‑4 generations per season (Akhatov et al., 2013).

How to recognise damage?

The caterpillars of the diamondback moth (small, spindle‑shaped, greenish, up to 9 mm long) lead a hidden life. Young caterpillars burrow into the leaf tissue and make winding mines. Older caterpillars emerge onto the surface and eat the leaf, leaving only the upper skin intact, so the leaf looks "window‑pane" (Akhatov et al., 2013). Particularly dangerous are caterpillars that damage the apical bud and young leaves inside the head.

Why is it important to react quickly?

Diamondback moth is known for its ability to develop resistance to insecticides quickly. Therefore, it is extremely important to prevent its mass reproduction and to alternate products with different modes of action.

Gardener’s tip: Inspect leaves for "mines" – winding light spots on the leaf blade. At the first signs, treat plants with biological products based on Bacillus thuringiensis (e.g., "Lepidotsid", "Bitoxibacillin"). They act only on young caterpillars and are safe for beneficial insects.

Cabbage Aphid

Aphids are small sucking insects that form colonies on the underside of leaves, on stems, and in leaf axils. On cauliflower, the cabbage aphid (grey, with a waxy coating) and the greenhouse (peach) aphid are common.

How to recognise damage?

Aphids suck sap from leaves, causing discolouration, deformation (curling and wrinkling), and stunted growth. Leaves become sticky from the "honeydew" secreted by aphids – a sugary liquid on which sooty mould subsequently settles, covering the leaves with black coating (Akhatov et al., 2013).

Why are aphids so dangerous?

Apart from direct damage, aphids are vectors of many viral diseases (e.g., mosaic virus). Viruses, once in the plant, cause systemic disorders from which the plant cannot recover (Akhatov et al., 2013). In addition, sooty mould impairs photosynthesis.

Gardener’s tip: Regularly inspect the underside of leaves. When first colonies are found, you can wash them off with a strong jet of water or treat plants with a soap solution (200 g of laundry soap per 10 L of water). Attracting natural enemies of aphids – ladybirds, lacewings, hoverflies – is the best long‑term strategy. For this, plant nectar‑producing plants (dill, fennel, buckwheat) near the cabbage.

Thrips (Tobacco Thrips)

Small (up to 1.5 mm) insects with fringed wings. Thrips are hidden pests that feed on plant sap. The most dangerous is tobacco thrips, which attacks over 400 plant species, including cabbage.

How to recognise damage?

Thrips suck sap from leaves, causing yellowish and then brown spots and streaks – "silvery" areas with black dots of excrement (Akhatov et al., 2013). Damaged leaves become deformed, smaller, and dry out. On cauliflower, thrips often hide between leaves and are difficult to see. In hot, dry weather, their numbers increase sharply.

Why are thrips dangerous?

Thrips damage reduces the marketable appearance of heads. In addition, they are vectors of dangerous viruses (e.g., tomato spotted wilt virus). Adults are very mobile and spread quickly.

Gardener’s tip: Use blue or yellow sticky traps for monitoring and catching thrips. Practice crop rotation and destroy plant residues. In hot, dry weather, carry out overhead watering in the evening – this creates unfavourable conditions for thrips. If necessary, use insecticides, alternating them to prevent resistance.

Ceutorhynchid Weevils (Cabbage Stem Weevil and other species)

These are small beetles (weevils) with a characteristic elongated head – a "snout". Ceutorhynchid weevils are among the most insidious pests because their larvae develop inside plant tissues, remaining invisible to the eye.

How to recognise damage?

• Adult beetles in spring gnaw small holes in leaf petioles and thick veins, and then lay eggs in the tissues (Akhatov et al., 2013). Small swellings (galls) appear on the petioles and stems – these are sites of larval development.
• Larvae are white, legless, up to 5 mm long, living inside petioles and stems, tunnelling through them. Externally, this manifests as wilting and drying of individual leaves. The most dangerous is that larvae can penetrate the growing point and destroy it from within.
• The main sign for the gardener is the detection of wilting of central leaves for no apparent reason, as well as small swellings at the base of petioles.

Why is this so dangerous?

Larvae of ceutorhynchid weevils live inside the plant and are inaccessible to contact insecticides. Damage to the growing point at the seedling stage can lead to the plant not forming a head at all or forming an ugly, loose head with several "tops".

Gardener’s tip: Carefully inspect seedlings before planting. Remove plants with signs of wilting and swellings. In autumn, be sure to remove and destroy all plant debris where beetles and larvae may overwinter. Deep digging of the soil also helps reduce the number of overwintering pests.

Caterpillars Damaging the Growing Point

Some species of caterpillars, primarily the cabbage cutworm, as well as diamondback moth, can deal a critical blow to the growing point. Unlike white butterfly caterpillars, which prefer to eat leaves from the edges, cutworm caterpillars often penetrate the very heart of the plant.

How to recognise damage?

• Cabbage cutworm caterpillars are thick, naked, greyish‑green or brown, up to 50 mm long. During the day they hide at the base of the plant or in the soil, and at night they come out to feed. They are capable not only of eating leaves but also of boring deep tunnels into the stem and reaching the growing point, completely destroying it (Akhatov et al., 2013). The presence of large, ragged holes in the central leaves and signs of excrement are a sure sign of cutworm activity.
• Diamondback moth caterpillars, especially under high population densities, can also damage the apical bud. They burrow into young leaves inside the rosette, causing them to deform and die. Outwardly, this looks like a cessation of growth of the central shoot.

Why is it important to notice in time?

Cutworm caterpillars are especially dangerous because they are nocturnal. The gardener may see a perfectly healthy plant during the day and find in the morning that the "heart" has been completely destroyed.

Gardener’s tip: Regularly inspect plants in the evening and early morning hours. If you notice damage atypical for whites (large ragged holes in the centre of the rosette, wilting of the apical bud), it may be cutworm activity. Use pheromone traps to monitor moth flights. When caterpillars are detected, use biological products (e.g., based on Bacillus thuringiensis), but treatments are best done in the evening when caterpillars come out to feed.

Other Causes of Growing Point Damage

It is important to remember that growing point damage may not only be caused by insects. Two most common non‑infectious causes are:

1. Damage by cruciferous flea beetles. As mentioned in Chapter 2, flea beetles can destroy the apical bud, especially on young seedlings. In this case, a flat "platform" forms at the site of the growing point, and the plant begins to produce lateral shoots (Starcev, 2021). It is easy to distinguish such damage from insect damage: flea beetles leave no excrement or tunnels inside tissues.

2. Exposure to low temperatures. Late spring frosts or sharp temperature fluctuations can cause the death of the growing point. This looks like blackening and drying of the central leaves. Unlike insect damage, frost injury has no signs of pest activity (excrement, slime, tunnels), and damage is often massive, simultaneous, and tied to a specific cold spell.

Gardener’s tip: Before applying insecticides, make sure that the damage is not caused by frost or other abiotic factors. If the growing point is damaged but the plant is not dead, you can try to save the crop by allowing the plant to form a head from side shoots. Although such heads will be smaller and may mature late, this is better than nothing.

Caterpillars Inside the Head

Caterpillars are the most dangerous pests of the head. They not only eat the inflorescences but also contaminate them with excrement, making the product unfit for sale and consumption. Most often, caterpillars of the cabbage cutworm and, less frequently, the small white, are found in cauliflower heads.

How to recognise damage?

Cutworm caterpillars, which are usually nocturnal, gnaw deep tunnels in the heads, leaving excrement inside (Akhatov et al., 2013). These tunnels serve as entry points for infections – when moisture gets in, the heads quickly rot. White butterfly caterpillars more often feed on the surface but can also penetrate inside. Their presence is betrayed by characteristic "eating" of the inflorescences, as well as the presence of excrement on the surface of the head.

Why is this so dangerous?

Caterpillars, especially cutworms, can completely destroy a head within a few days. In addition, their excrement, getting between the inflorescences, is extremely difficult to remove during cleaning, making the product unfit for sale.

Gardener’s tip: Start regular inspections of heads from the moment they set. Inspect not only the surface but also part the leaves to look inside. If you notice damage or signs of excrement, and the caterpillars are not visible (they may hide in the soil during the day), treat the plants in the evening with biological products based on Bacillus thuringiensis (e.g., "Lepidotsid", "Bitoxibacillin"). These products act on the caterpillars through the intestine, and they stop feeding within a few hours.

Aphids Inside Leaves and the Head

Aphids are sucking insects that can also colonise the head, especially if it has already begun to form. Aphids prefer young, tender tissues and hide between inflorescences and under the leaves covering the head.

How to recognise damage?

The presence of aphids on the head is betrayed by the sticky honeydew they excrete. This attracts ants and promotes the growth of sooty mould, which covers the head with black coating (Akhatov et al., 2013). The head itself may become deformed, its growth slows down, and the inflorescences become loose.

Why is this dangerous?

Aphids not only reduce the quality and appearance of the product but also, as mentioned, are vectors of viruses that can cause systemic disorders, which is especially critical for such a delicate organ as the head. In addition, honeydew and sooty mould make the head unattractive to buyers.

Gardener’s tip: Regularly inspect heads for aphids. At the beginning of infestation, aphids can be washed off with a strong jet of water or treated with a soap solution. In case of severe infestation, use approved insecticides, but remember the short pre‑harvest interval. The best strategy is prevention: protecting plants with row covers and attracting natural enemies of aphids (ladybirds, lacewings) by planting nectar‑producing plants near the cabbage.

Thrips

Thrips, especially tobacco thrips, can also attack cauliflower heads. They prefer hidden places and easily penetrate between inflorescences and under wrapper leaves.

How to recognise damage?

Thrips feed on cell sap, causing small silvery‑white spots and streaks, as well as black dots of excrement on the head (Akhatov et al., 2013). The damaged head loses marketable appearance, becomes spotted, and with severe infestation – deformed.

Why is this dangerous?

Thrips are hidden pests, difficult to notice at the initial stage of infestation. Moreover, they are vectors of viruses. Mass reproduction of thrips occurs in hot, dry weather, so during such periods the risk of head damage increases.

Gardener’s tip: Use blue or yellow sticky traps to monitor thrips numbers. In hot, dry weather, carry out evening overhead watering – this creates unfavourable conditions for these pests. If necessary, apply approved insecticides, alternating them to prevent resistance.

Slugs

Slugs are nocturnal pests that can also damage the head. This occurs especially often under high humidity conditions, when the head forms in rainy and cloudy weather.

How to recognise damage?

Slugs gnaw irregularly shaped holes in the head, leaving characteristic silvery mucous trails (Akhatov et al., 2013). Slug damage often appears as shallow, wide, ragged ulcers.

Why is this dangerous?

Slugs can greatly spoil the appearance of the head in one night, making it unfit for sale. Like caterpillars, they leave excrement that contaminates the inflorescences.

Gardener’s tip: Regularly inspect plants in the evening hours. Create unfavourable conditions for slugs: avoid dense plantings, remove weeds, do not over‑moisten the soil. Use traps – moist pieces of boards or slate under which slugs gather during the day. If necessary, scatter approved products based on iron phosphate around the plants.

Additional Tip

The importance of regular head inspection. The best protection for the head is regular and careful inspection. The cauliflower head forms quickly, and pests can appear at any moment. As soon as you notice the first signs of head set (the appearance of a small white "button" in the centre of the rosette), start daily inspections. This will allow you to notice a problem in time and take action before the damage becomes critical.

Holes in Leaves

Leaf damage is the most common and noticeable symptom. However, the nature of the holes varies greatly.

What do the damages look like?

• Small, pinpoint holes and ulcers, as if the leaf was shot with buckshot. This is the classic sign of cruciferous flea beetle activity. The beetles gnaw small pits in the leaf, leaving a characteristic dotted pattern (Akhatov et al., 2013; Starcev, 2021). In severe damage, the leaf may be completely skeletonised.
• Large, ragged, irregularly shaped holes along the edges and in the centre of the leaf. This is the work of caterpillars – whites (large and small) and cutworms. Young caterpillars first scrape the flesh from the underside, leaving "windows", while older ones eat the leaf from the edge towards the centre (Akhatov et al., 2013). Cutworms can bore deep tunnels in stems and stalks.
• Irregular holes with ragged, uneven edges, often combined with silvery mucous trails. This is the work of slugs. They gnaw tissues along the edges and in the middle of the leaf, leaving a characteristic "eaten" appearance (Starcev, 2021).

What to do next?

If you see small pinpoint damage – look for small jumping beetles. If the damage is large and ragged – look for caterpillars on the underside of leaves or at the base of the plant. If there is slime – it is slugs, and you need to look for them at night or under shelters.

Excrement

The presence of excrement is a sure sign that a pest is feeding on the plant.

What does the excrement look like?

• Small, dark, crumbly balls or pellets. These are excrement of white and cutworm caterpillars. They can be found on damaged leaves, inside the head, or on the soil under the plant (Akhatov et al., 2013).
• Black, oily, often sticky dots on the leaf. These are excrement of thrips. They resemble fine black pepper and are clearly visible on the silvery background of damaged tissue (Akhatov et al., 2013).
• Sticky, shiny secretions (honeydew). This is the waste product of aphids. Honeydew covers the leaves, making them sticky and shiny. Black sooty mould often develops on it.

What to do next?

Having found excrement, carefully inspect the plant to find their "author". Caterpillars are often found on the underside of leaves or inside the head. Aphids and thrips are small; you need to look for them with a magnifying glass, especially on the underside of leaves and in the axils.

Silveriness

Changes in leaf colour and texture are important diagnostic signs.

What does silveriness look like?

• Silvery, greyish, or whitish spots and streaks on leaves, often with black dots. This is a characteristic sign of thrips infestation. Thrips suck sap from individual cells, causing them to die. As a result, the tissue becomes silvery or whitish (Akhatov et al., 2013).
• Silvery, dried trails (slime) on leaves and heads. This is a characteristic sign of slug activity. The slime they secrete when moving dries and leaves a noticeable silvery shiny trail (Starcev, 2021).

What to do next?

Silvery spots with black dots – look for thrips on the underside of leaves. Silvery trails – look for slugs in the evening and night hours.

Leaf Curling

Leaf deformation is often the result of sucking pests.

What do curled leaves look like?

• Leaves curl downward, become wrinkled and deformed. This is a characteristic sign of aphid infestation. Aphids suck sap, and leaf tissues stop growing evenly, leading to curling and deformation (Akhatov et al., 2013). Curling can also be caused by viruses that aphids transmit.
• Leaves curl upward, become cup‑shaped and brittle. This may be a consequence of damage by diamondback moth at early stages or by other hidden pests damaging the growing point.

What to do next?

Inspect the underside of curled leaves. If there are aphid colonies – the culprit is found. If there are no aphids, the growing point may be damaged, and you need to look for other signs (wilting of central leaves, tunnels in stems).

Growth Stunting and Wilting

These are the most alarming symptoms because they often indicate damage to the root system or growing point.

How does stunting manifest?

• The plant wilts even with sufficient watering, lags in growth, and is easily pulled out of the ground. This is a sign of damage to the root system by cabbage fly larvae. The larvae tunnel through roots and stems, disrupting water and nutrient uptake (Akhatov et al., 2013; Starcev, 2021).
• Cessation of growth of the central shoot, appearance of many side shoots instead of one. This may be a consequence of damage to the growing point by ceutorhynchid weevil, diamondback moth, or flea beetles (Starcev, 2021). Instead of one large head, several small, unmarketable ones form.
• Sudden wilting without other signs. This may be the result of damage by mole crickets, which gnaw roots underground, or stem damage by cabbage cutworm.

What to do next?

If a plant wilts, carefully pull out one of them and inspect the roots. White larvae in the roots – cabbage fly. Damaged, chewed roots – mole cricket or wireworm. If the roots are intact and the growing point is damaged, look for signs of hidden pests inside the stem or petioles.

Diagnostic Table: Quick Identification of the Culprit

Gardener’s tip: When inspecting plants, pay attention not only to the damage but also to its "authors". Caterpillars and beetles can be seen with the naked eye, while a magnifying glass will be needed to find aphids and thrips. Careful observation and knowledge of symptoms are the key to successful crop protection.

Prevention: The Foundation

Prevention is the most important, most effective, and most environmentally friendly method of protection. It requires time and attention at the initial stage but pays off handsomely, reducing the need for emergency chemical treatments.

1. Crop rotation and spatial isolation. This is the golden rule of plant protection. Pests and diseases specialised on brassica crops accumulate in the soil and on plant residues. It is recommended to return cauliflower to the same place no earlier than after 3‑4 years (Courtens, 2025; Starcev, 2021). Also try to place cauliflower plantings as far as possible from last year's plots with cabbage, radish, turnip, and other crucifers. This hinders the spread of pests, especially diamondback moth and cutworms.

Why does it work? Most pests have limited mobility. If you remove their food source, they cannot build up high numbers. In addition, eggs, larvae, and pathogen spores overwinter in the soil and plant debris. Crop rotation breaks this cycle.

2. Destruction of weeds and plant residues. Cruciferous weeds – shepherd's purse, wild mustard, wild radish, field mustard – are reservoirs for many pests and diseases (Akhatov et al., 2013; Starcev, 2021). They provide additional food and breeding opportunities for pests before cultivated plants appear. In autumn, be sure to remove and destroy all cabbage plant residues. Deep digging of the soil also helps destroy overwintering stages (cutworm pupae, false cocoons of cabbage fly, slugs).

Why does it work? By depriving pests of alternative food sources and overwintering sites, we reduce their overall numbers in the area.

3. Choosing healthy seedlings and resistant varieties. Start with quality planting material. Buy seedlings from trusted suppliers or grow them yourself in clean, sterile soil. Carefully inspect seedlings before transplanting – discard wilted, yellowed, with damaged leaves or suspicious swellings on roots. Prefer varieties and hybrids that have good tolerance to the main diseases and pests in your region.

4. Optimal planting dates. Early transplanting of seedlings into the ground allows the plants to root and strengthen before the mass emergence of the main pests, such as cabbage fly and flea beetles (Starcev, 2021). For summer plantings, use varieties resistant to heat and diseases.

5. Row covers. This is one of the most effective and environmentally friendly solutions for protecting cabbage at early stages. Non‑woven material (spunbond, agrotex, agrospan) or fine mesh stretched over hoops immediately after transplanting creates a physical barrier for butterflies, flies, flea beetles, and aphids (Courtens, 2025). The cover can be kept until the plants are strong and begin to set heads.

Why does it work? Row covers simply prevent pests from reaching the plants. This is especially effective against white butterflies and diamondback moths, which lay eggs on leaves.

Monitoring and Observation

Even with the most careful prevention, pests can appear. It is important to notice them in time.

1. Regular inspections. Carry out inspections of plantings at least 1‑2 times a week, and during head formation – daily. Inspect not only the upper but also the lower side of leaves, growing points, leaf axils, and the heads themselves. Pay attention to any changes: holes, curling, colour changes, wilting, presence of excrement or slime.

2. Use of traps. Sticky traps (yellow and blue) will help to detect the appearance of thrips and aphids in time (Courtens, 2025). Pheromone traps allow you to monitor the flight of cutworm and moth butterflies to start treatments on time. Traps are placed at plant level and checked 1‑2 times a week.

3. Knowledge of symptoms. Use the knowledge from the previous chapter (Chapter 6: How to Identify the Pest by Symptoms) to quickly and accurately diagnose the problem. The earlier you identify the pest, the easier it will be to deal with it.

Active Measures: From Biological to Chemical

When prevention and monitoring have not yielded results and the pest population has reached the economic injury level, it is time for active measures.

1. Biological methods. This is the safest way of control for humans and the environment.

• Attracting entomophages. Ladybirds, lacewings, hoverflies, aphidius wasps – these are natural enemies of aphids, caterpillars, and other pests. Attract them to the site by planting nectar‑producing plants (dill, fennel, buckwheat, phacelia) near cabbage beds (Akhatov et al., 2013). Avoid the use of broad‑spectrum insecticides that kill beneficial insects as well.
• Biopesticides. Products based on the bacterium Bacillus thuringiensis (Bt, e.g., "Lepidotsid", "Bitoxibacillin", "Dendrobacillin") are highly effective against young caterpillars. They act selectively, affecting only the gut of caterpillars, and are safe for humans, animals, and beneficial insects (Akhatov et al., 2013). Important: Bt works only when caterpillars eat treated leaves, so treatments should be carried out when caterpillars are actively feeding, and all parts of the plant should be thoroughly covered.

Why do biopesticides work? Bacillus thuringiensis produces a crystal protein that, in the caterpillar's gut, turns into a toxin and destroys its walls. The caterpillar stops feeding within a few hours and dies within 2‑5 days.

2. Mechanical methods. These are simple and effective ways, especially on small plots.

• Manual collection. Regularly inspect plants and manually collect caterpillars, white butterfly egg clusters, adult beetles (e.g., rape blossom beetle). This is labour‑intensive but very effective at low pest numbers.
• Slug traps. Under pieces of boards, slate, or dark film laid on wet soil, slugs gather for daytime rest. They can be easily collected and destroyed (Starcev, 2021). You can also use beer traps or special granules based on iron phosphate, which are safe for pets.
• Washing off aphids with a jet of water. A strong jet of water from a hose can wash aphids off leaves. This method is effective at early stages of infestation.

3. Chemical methods. This is a last resort, to be used only when other methods have failed and the pest population threatens the crop.

• Choice of product. When choosing an insecticide, it is important to accurately identify the pest and use a product registered for its control. Prefer selective products that cause minimal harm to beneficial insects over broad‑spectrum ones. Alternate products with different modes of action to prevent the development of resistance in pests (Courtens, 2025).
• Compliance with regulations. Strictly follow the dosage, timing, and frequency of treatments indicated on the label. Observe the pre‑harvest interval (the period between the last treatment and harvest) to avoid harmful substances entering the food.
• Features of head treatment. During head formation, try to use only biological products or products with a short pre‑harvest interval. If it is necessary to use a chemical insecticide, apply it in the evening when beneficial insects are less active.

Gardener’s tip: Start with preventive measures and regular monitoring. Use biological products at the first signs of pests. Resort to chemicals only as a last resort, when the crop is under direct threat. Remember that healthy, well‑developed, and well‑cared‑for cabbage is less attractive to pests and tolerates damage better.

We hope this article helps you successfully grow a healthy and tasty cauliflower crop, and your knowledge will help you deal with any pests. Good luck in the garden!