Discovering scale insects on your plant is not only annoying, but also requires quick action - scale insects can quickly spread to other plants and cause a lot of destruction. In this article we have summarized how you can fight scale insects effectively and permanently.

Scale insects are often very small and hidden

Table of Contents

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  1. the essentials in brief
  2. identify scale insects
  3. fight scale insects
  4. Mechanical removal
  5. home remedies
  6. Chemicals
  7. Beneficial against scale insects
  8. Prevent scale insects
  9. affected plants

    10. the essentials in brief

    • Scale insects are difficult to recognize at first; sticky plaque indicates an infestation
    • Scale insects can be easily combated with household remedies such as oil, washing-up liquid, garlic or milk
    • Beneficial insects such as parasitic wasps, (22.99€) ladybugs or hoverflies are good helpers in the fight against scale insects

    How to recognize a scale insect infestation

    In most cases it is not difficult to recognize a scale insect infestation on your plant. Unfortunately, the pests are not easily and clearly visible from the start, so damage has often already occurred before the plant shows any signs of infestation. Look for signs that the leaves are sticky on the upper side or that a whitish coating is developing. This sticky substance is the "honey" of scale insects. This honey also attracts ants, for example, so their appearance is another sign of the presence of scale insects. Other indications can be encrusted shoots, deformed flowers and leaves as well as discoloration or loss of leaves.

    Many ways and means of combating possible

    In order to combat scale insects effectively and permanently, you should act quickly after detecting the infestation, not only to save the plant itself, but also to prevent infestation of other plants nearby. The following immediate measures can help:

    • Isolate the affected plant (if possible) and provide a light and cool quarantine. Cold can already help to get rid of scale insects;
    • Remove severely damaged or dead shoots and flowers;
    • Rinse hardier plants with water.

    In addition to the immediate measures to prevent spread, a suitable means of driving out the pests must be selected. There are a variety of products and procedures that come into question. The selection always depends on how severe the infestation is, what kind of plant it is and whether it is indoors or in the garden. In many cases, a home remedy can also be used, so that chemicals can often be dispensed with. There are also options for manual, biological and chemical control and the use of beneficial insects.

    Scale insects can be reduced with a strong shower

    Toothbrush and water: mechanical removal

    In most cases, the mechanical removal of scale insects does not work as a stand-alone method of control, but can be used as a first immediate measure, especially in the case of a heavy infestation. For garden plants, grab a water hose and toothbrush, or for indoor plants a wet washcloth, and begin by hand to rinse the foliage completely, rinsing away the honeydew and any visible scale insects. The toothbrush or rag should then be scrubbed across the entire plant at right angles to the branch or twig.

    Make sure, however, that you only apply as much pressure as your plant can bear without further damage - it is better to avoid mechanical removal if the plants are sensitive. Citrus plants and palm trees, for example, benefit greatly from this measure because treatment with a toothbrush does not affect them. It is best to repeat the process again after a few days to be sure you have removed all the critters.

    Insider tip: Use home remedies

    Mealybugs and scale insects can also be systematically combated with many home remedies, which opens up a multitude of possible approaches. It is best to test the selected home remedy on an inconspicuous leaf after mechanical removal before treating the entire plant - this will prevent the plant from being further damaged by an intolerance. The following home remedies are particularly suitable for controlling scale insects:

    • Oil;
    • alcohol and alcohol;
    • soap and washing-up liquid;
    • other plant products;
    • coffee, tea and milk; such as
    • tobacco or nicotine.

    Various oils

    On the side of organic home remedies, various oils have proven to be useful pesticides against scale insects. The structure of the oil clogs the airways of the scale insects, which is why they suffocate within a short time. Since oil is not a contact poison, you can benefit from quite natural control. Use canola oil, tea tree oil, neem oil, or olive oil and smear it on visible critters every day for two weeks until scale insects are gone. Since this process is lengthy, it is recommended in combination with other home remedies. You can also speed up the process by mixing the oil with water and spraying it all over the plant.

    spirit and alcohol

    You should be careful when using alcohol, as many sensitive plants could be damaged by it. Alcohol is particularly recommended if your plant has a thick skin - such as cacti or palm trees. Mix high-proof alcohol or denatured alcohol with a little water and squeeze the mixture onto each individual scale insect while the infestation is fairly small. The mixture penetrates the pests' armor and kills them. Subsequent repotting is strongly recommended.

    soap and washing-up liquid

    A mixture of detergent, water and vinegar can also help. Spray the affected plant completely with this mixture and leave it on for a few hours before giving the plant a good shower. Various effective combinations are possible here: for example, pure vinegar or soapy water or a mixture of water, dishwashing liquid and alcohol will work if the plant is more robust.

    Make sure that the soap you use is free of fragrances and other artificial additives so that the plant can be treated as gently as possible. So a good practice is to use straight curd soap and dissolve it in water to make your own dish soap. Soft soap (€44.90) is even better for making soapy water, as it dissolves more quickly in water due to its consistency.

    Soapy water is an efficient home remedy for scale insects

    Use other plants: garlic or nettle

    In addition to the other biological approaches and home remedies, there is also the possibility of using the power of plants for your own purposes. For example, a small infestation can be contained if you stick garlic cloves in the soil of a potted plant, which will repel the garlic-hating pests. Alternatively, you can boil a broth with chopped garlic and apply it with a spray bottle.

    Especially in the garden it is a good idea to make manure from nettles. It is not advisable to do this indoors, as the liquid manure develops a strong odour. Cover and soak nettles in a large container of water for three days, stirring daily. Then filter the resulting manure and apply it repeatedly to the affected plants.

    coffee, tea and milk

    All coffee and tea drinkers can also use their habit to also make their own home remedy for pest control. Take the cold leftover coffee grounds or the cold, brewed tea leaves and mix them with water and then spray the mixture generously onto the plant. A combination of tea and coffee has also proven to be effective - and creates a pleasant scent in the home. You can also add the coffee grounds directly to the soil in the pot, where they act as a pest repellent and fertilizer. Alternatively, a mixture of milk and water can be used. For this purpose, however, the milk should be boiled briefly beforehand and then poured cold over the plant.

    tobacco or nicotine

    As a last home remedy, the use of tobacco or nicotine is possible. Pour hot water over tobacco or cigarette ash and let the mixture sit for about an hour before straining and brushing or spraying on the affected plant. Tobacco or cigarette ash on the potting soil can also enhance the desired effect. But caution is also required here: this procedure is not for sensitive plants!

    Special combat from the trade

    In addition to combating scale insects with home remedies, which in some cases can be done without chemicals, there are also special pest and plant protection products available in specialist shops. The advantage of these agents is that they are particularly effective and the fight is therefore permanent and effective. Be careful not to use biological contact poisons such as pyrethrum, as these cannot penetrate the scale insect's shell and are not very effective, but could have a negative effect on other insect species in the garden. Beneficial insects are also commercially available, which, depending on the type of scale insect, can be exposed to the plant as natural predators.

    These tools are suitable

    Suitable agents for chemical control are, above all, ready-to-use oil-based sprays such as Neudorff Promanal. This remedy smothers the pests, gives the leaves a beautiful shine and at the same time does not affect other endangered insects (such as bees). Lizetan-based sprays can also be used effectively for control purposes. Lizetan is particularly gentle, so it can also be used on sensitive plants such as orchids. The spray not only reaches the visible scale insects, but also the hidden pests, which is why a single treatment is sufficient in many cases. Sticks with this active ingredient can also be used for indoor plants.

    For experts: use beneficial insects

    Scale insects can also be combated with beneficial insects

    Finally, there is the possibility of putting scale insects "on the shell" with the targeted use of beneficial insects. However, this procedure requires some expert knowledge, since not every type of scale insect is fought with the same beneficial insects. The advantage, however, is that this is a particularly natural way of pest control. It is best to contact a specialist so that they can help you determine the species of scale insect and select the beneficial insect. In most cases, one of the following types of insects is then resorted to:

    • parasitic wasps;
    • ladybug;
    • hoverflies; or
    • predator beetle.

    Good plant care can prevent scale insects

    If your plant is being attacked by scale insects, this is in most cases a symptom: scale insects mainly infest plants that are not in good condition. Therefore, a scale insect infestation is more common, especially in winter or spring, when the plants have had to get by with little light. If you have to fight scale insects, it is advisable to also prevent a new infestation and to pay particular attention to the care of the plant after elimination. These include the following measures:

    • Make sure your plant gets enough light;
    • With indoor plants, pay attention to the indoor climate and avoid letting them get too warm;
    • Avoid nutrient deficiencies and use small amounts when fertilizing with nitrogenous products;
    • The soil must be sufficiently loosened;
    • Water with sufficient water and make sure that there is no accumulation of waterlogging.

    In the case of fruit trees in particular, it can also be useful to treat the trunk with suitable care and to encourage the proliferation of beneficial insects in the garden.

    background

    There are many types of scale insects

    Not all scale insects are the same: in fact, there are over 4,000 different species of this pest that infest and destroy plants. If you have found an infestation, it is worth taking a closer look at the culprit as a first step. The color and shape of the shell gives information about the species. It is often the case in our latitudes that one of the following scale insect species is responsible for damaging your plant:
    • lid scale: These black, blackish-brown to brown scale insects are characterized by a flat operculum that can be easily detached with a pin. They belong to the largest group of scale insects and are very widespread.
    • scale insect: Scale insects are also widespread and are black, black-brown or brown in colour, and in some cases also reddish. In contrast to the lid scale, however, the lid is arched and attached to the dorsal skin, so that it cannot be lifted.
    • comma scale insect: These gray to white scale insects have an elongated, slightly curved lid and are mainly found on fruit trees. The name comes from the shape of the pest.
    • cochineal scale insect: Cochineal scale insects have a crimson body coated with a white to gray wax. Because their body contains a high concentration of carminic acid, the pests appear bright red when crushed.
    • Mealybug: This is a subspecies of scale insects that can be easily identified as it produces and leaves a substance on the leaves that looks like small white cotton balls.
    • aphids: In contrast to scale insects, these pests are significantly smaller and differ in appearance from scale insects. Along with snails, they are one of the most common pests in the garden.

    There are many different types of scale insects

    Omnivorous scale insect: various plants can be affected

    Mealybugs and scale insects are not gourmets, but real omnivores. They can occur on almost any tree and crop species, regardless of whether they are in the garden or indoors. In fact, there are some plant species that are particularly popular with scale insects. These include the following in particular:

    • citrus plants: orange trees, lemon trees.
    • fruit plants and other tree species: blueberry bushes, currant bushes, yew trees, olive trees.
    • indoor plants: Yucca palms, ficus or benjamini, dracaena or dragon tree, cacti, rubber trees, orchids, poinsettia.
    • Outdoor and hedge plants: boxwood, laurel and laurel cherry, ivy, hydrangea, camellia, oleander, roses, vines or infestation of entire vineyards.

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Animals in the garden