Scale insects are among thePests in the garden. Their sticky traces are a sure sign that there is an infestation. In the article we explain how you can fight scale insects and which home remedies can help.
1. Recognize scale insects: What do scale insects look like?
The scale insect species that can be found in Germany have a body length of 0.8 mm to 6 mm. The males have wings and look like small flies. The females, on the other hand, are mostly immobile and spend their entire lives on the plant. They feed on the plant juices that they absorb through their mouthparts. They are yellow-brown in color and lay their eggs directly on the plant. The larvae, which hatch in mid-summer, are mobile and also feed on the plant juices. They excrete honeydew, which attracts ants.
1.1.How can you recognize a scale insect infestation?
The first sign of an infestation is the sticky secretion that can be found on the underside of plant leaves, shoots or twigs. The leaves of the affected plant are shiny and stick together. In some cases, the flowers may wilt and the leaves may turn yellowish. Honeydew, the sticky substance that adult females produce, can be found not only on the plants themselves, but also on furniture and the ground. Ants are often attracted to it because honeydew is the perfect food for them. Incidentally, the scale insects can easily overwinter both indoors and outdoors. They are protected from the elements by a shell.
1.2.How do scale insects get into the apartment?
Garden experts have long known how scale insects spread in the garden. The mobile larvae in particular are carried away by the wind. Some larvae simply migrate and look for other plants. With a hot summer and mild autumn, several generations can grow up. This is also the reason why they can attack all plants in the bed in just one gardening season.
However, many people ask themselves how pests get into their homes. There are several variants:
- Most of the time the scale insects are transported with a new plant. When buying new plants, always check the underside of the leaves for scale insects.
- The larvae can also be introduced with the plant soil. Yes, scale insects can also be found in the soil. The reason for this is very simple. Some scale insects attack plant roots. This is why their larvae stay in the plant substrate.
- Ants can also contribute to the spread of scale insects. They often take the larvae with them to new plants.
1.3. Are scale insects dangerous to people?
Scale insects are generally not dangerous to humans. The most important thing is to fight the pests naturally and avoid chemicals. The majority of these chemical agents are harmful to humans and animals and there are preparations that are even banned because they can leach into groundwater. Anyone who violates the rules must expect a fine. Fortunately, you can avoid it because there are also home remedies or natural control products that you can use to get rid of the pests.
2. Fight scale insects: Which garden and house plants are affected?
Scale insects are very adaptable. While the pests spread outdoors in the summer months, indoor plants are mostly attacked in the cold season. It is enough if just one potted plant with scale insects is brought into the glasshouse or winter garden. Therefore, the first step in controlling aphids is prevention. Check regularly whether all houseplants are healthy. Possible reasons why a plant is affected by scale insects:
1. The plant is weakened. Possible reasons: Incorrect location, inadequate care, too much fertilizer with nitrogen.
2. The winter quarters are too warm. This can promote the spread of the larvae and the reproduction of scale insects. Place your houseplants in a bright and cool place.
3. There is not enough sunlight. This causes the plant sap to change and be preferred by the scale insects.
2.1. Scale insects on the lemon tree
Lemon plants are often attacked by scale insects. This is mainly because they are often put in the wrong place. Especially in winter, a winter quarter that is too warm and too dark can weaken the tree. There are basically two options for wintering to choose from:
1. Overwintering in a warm and very bright location (the winter garden, a room with large windows and a south or west orientation). Temperatures should never fall below 20° Celsius.If the lemon treeIf it is not overwintered in a dark place, then it needs regular fertilization in the winter too.
2. Overwinter in a cool, dark place (in a garden shed or a bright garage). The temperature in the room should be between 4° and 14° Celsius. Very important: Place the plants on a Styrofoam plate so that the roots do not freeze and can absorb moisture.
No matter which option you choose: the humidity should be around 40%. If you ventilate the room even on warm autumn and winter days, the citrus tree will feel comfortable and survive the winter healthy.
For a mild infestation: Scrape off the pests with a toothbrush, repot and rinse the roots thoroughly to remove any remaining larvae. Be sure to overwinter the infected plant separately from other houseplants.
In case of a severe infestation: Place in a sunny location, scrape off the pests and repot the plant. Ventilate regularly and do not provide the tree with nitrogen fertilizer. For home remedies and beneficial insects that help against scale insects, see below.
Home remedies:Spray with rapeseed oil or orange oil.
2.2. Scale insects on palm trees
Pests quickly spread on diseased palm trees. In this case too, the following applies: Overwinter the plant in a dark, cool place with appropriate humidity. In this case, the composition of the plant juices remains unchanged and the exotic is for theAphids less attractive. By the way, if you have a lot of palm trees, you should leave enough space between the pots.
For a mild infestation: Scrape off the scale insects, repot and rinse the roots under running water.
In case of a severe infestationplace the palm tree in a sunny place with high humidity. For home remedies and beneficial insects that help against scale insects, see below.
home remedies: Dishwashing liquid solution and soft soap
2.3. Scale insects on the olive tree
The olive tree is often attacked by pests because it is often not cared for properly.For a mild infestationIt is enough if you scrape off the scale insects and strengthen the potted plant with mycorrhizal fungi. The fungal spores are sold as substrate and must be buried near the plant roots. This soil fungus can improve nutrient absorption and regulate the composition of plant juices. This strengthens the olive tree.
In case of a severe infestationPruning can help, with only the affected parts of the plant being cut off. You can then treat the tree with a home remedy.
Home remedies:Solution with soft soap (see below)
2.4. Scale insects on oleander
The oleander is very sensitive and can die quickly. To prevent this, check your houseplants regularly for pests. It is often enough to remove the scale insects with a toothbrush.When the pestsIf you have made it wide, cutting it back can help.
Home remedies:You can treat the plant with a homemade spray containing orange oil. (see below)
2.5. Fight scale insects on orchids
If your orchids have scale insects, you should act as quickly as possible before the pests spread. Proceed as follows: First scrape off the scale insects with a toothbrush, then cut off the bracts of the affected flowers. You can then treat the remaining orchid leaves, shoots and stems with a home remedy.
Suitable home remedies:Orange oil
2.6. Fight scale insects on hydrangeas
If you want to combat scale insects on hydrangeas, you can take the following measures:
1. Loosen the soil around the plant roots.
2. Mulch.
3. If there is a severe infestation, you can fight the scale insects with beneficial insects.
3. What helps against scale insects? Home remedies and beneficial insects
If you want to combat scale insects, you can drive them away with beneficial insects or you can treat the plants with home remedies. Below we take a closer look at the different variants.
3.1. Beneficial insects against scale insects
The scale insects not only attack ornamental plants, but can also cause major damage to kitchen gardens. So if you find the pests in the garden, you should act quickly. You can of course fight scale insects by introducing beneficial insects into your home garden. The following insects help:
- Parasitic wasps against scale insects
- CM-Australian ladybirds against mealybugs
- Ladybugs against scale insects
- (Earwigs help against aphids, which, however, do not belong to the superfamily of scale insects)
- Some species of birds
A naturally designed garden offers the best conditions for a great diversity of species. However, monocultures and gardens with only a few plant species can prove to be a real challenge. In this case, you can also find certain beneficial insects in garden centers. However, so that you can find the right beneficial insect that feeds on the larvae and the adult males and females, you should take a specimen of your scale insects with you to a specialist.
3.2. Fight scale insects: home remedies with soft soap
An effective home remedy against scale insects is a solution of soft soap and spirit. Fill 2 liters of water into a plastic container, add 30 ml of soft soap and 30 ml of spirit and let the solution sit for about half an hour to 45 minutes. Apply the solution to the leaves and shoots with a brush. It is worth testing the effect on the plant on a leaf first. If the leaf has not yellowed and fallen off the next day, then you can use it to treat the plant.
Important: A second treatment takes place approximately 10 to 14 days after the first. Never use on orchids or oleanders.
3.3. Fight scale insects with dish soap
Dishwashing liquid alone can't do much against scale insects. But the combination of an oil and dishwashing liquid can prove to be particularly effective. If you want to fight scale insects naturally, you can add 1 tablespoon of vegetable oil (olive oil works well for this purpose, but you can also use rapeseed oil) and 1/2 teaspoon of dishwashing liquid in 500 ml of lukewarm water. Stir the solution well and pour it into a clean spray bottle. Use it to wet the plant leaves (including the underside).
3.4. Is neem oil effective against scale insects?
Neem oil, which is extracted from the neem tree, is considered abiological poison for insects. However, the remedy is little or not at all effective against scale insects because they have a shell.
3.5. Orange oil against scale insects
The orange oil is very aggressive and takes effect quickly. It has another decisive advantage: In contrast to various other brews, it has no unpleasant smell and is also suitable for use in closed rooms. Add about 10 ml of orange oil to 500 ml of lukewarm water, pour the solution into a spray bottle and shake the bottle vigorously. Then test its effect on a leaf. If it doesn't die, you can spray the whole plant the next day. It is gentler if you brush the scale insects with the solution.
3.6. Fight scale insects with rapeseed oil
Rapeseed oil is gentler than orange oil and has a similar effect: if the plant is treated with it, the scale insects cannot breathe and suffocate. To ensure that the larvae are also controlled, you should treat the plant again after a week.
3.7. Fighting scale insects with coffee: is that possible?
The aphids can be effectively combated with home remedies using coffee grounds, as the caffeine they contain is poisonous to them. However, the scale insects have a shell and are therefore less or not at all susceptible. But you can brew the coffee grounds, strain them and use the water to water the plants. The scale insects will absorb the caffeine through the plant juices.
A few more natural remediescan be found here.
