Mealybugs - How to Get Rid of the Sticky Mealybugs

Fighting mealybugs successfully (mealybugs)

Recognize mealybugs and mealybugs

“The” mealybug does not exist, instead - like its close relative, the scale insect - there are around 1000 different species. Around 65 are classified as plant pests in Germany, with the citrus smear louse (Planococcus citri) being particularly common. It not only affects leaves and shoots, but also nests in the roots. This is why this variety bears the name Wurzellaus. You can recognize them by the numerous “cotton balls” on the root neck and in the root area.

Damage and symptoms

For a successful control, the specific type of the pest - which in any case cannot be determined by laypeople - is not important. You can recognize an infestation in all mealybugs by these symptoms:

Lice sit under a layer of white wax with threads similar to cotton balls
are often found on the undersides of the leaves
or in the Triebachseln
often also on the roots and on the root neck
Leaf spots, stunted and curled leaves
Leaves later dry up and fall off
Stunted growth and shrinkage of the plant in the event of severe infestation
white, greasy residue on and near the plant
sticky honeydew

The sticky residues are the sweet excretions of the pests called honeydew. These cause further problems, because they attract ants and are colonized by sooty or blackened fungi. If you notice increased activity of ants on certain plants, especially with garden plants, an infestation with woolly lice or other plant lice such as aphids or scale insects is not unlikely.

Tips

Simply wipe off sticky leaves and sooty mildew

If the leaves of the plants infected by mealybugs are covered with a blackish film, it is sooty mildew. This is a fungus that feeds on honeydew and only adheres superficially to leaves and shoots. Therefore, you can simply wipe off the base carefully with a cloth dipped in lukewarm water. You should do the same with the sticky residue left by the pests so that the photosynthesis of the affected plant is not disturbed.

These plants are particularly often infested

Mealybugs particularly like to sit on citrus plants such as a lemon or orange tree. But the pests can also often be found on orchids, cacti, palm trees and other indoor plants. In addition to hydrangeas, other herbaceous perennials and herbs are threatened with infestation in the garden.

Healthy and strong plants can usually defend themselves, but if the plants are weakened by an unsuitable location or incorrect care, an infestation is likely. Mealybugs and mealybugs occur mainly in warm, dry weather, for example in the summer months or, in the case of indoor plants, towards the end of winter.

Fighting mealybugs effectively - what really helps?

"Why should I use toxic (and expensive!) Chemicals when effective antidotes are growing in the garden?"

When it comes to combating mealybugs and effective crop protection, you have various options. Do not resort to the chemical club right away, even if it seems easier at first - toxic agents have a number of subsequent problems. Instead, we have put together some home remedies that have been tried and tested against plant vacuums here.

First aid measures

As soon as you have identified an infestation with mealybugs, isolate the affected plants - otherwise other houseplants will quickly become infected. Furthermore, these first aid measures help to prevent further spread:

rinse affected plants with a strong jet of water
Cut back heavily infected parts of the plant
collect isolated mealybugs, e.g. B. with the help of a toothbrush
Repot heavily infested plants and remove soil residues

Once you have completed these steps, take further action. In the following section you will find out which are useful and how to use them.

Make your own sprays - this is how it's done

Easily produced spray treatments based on have proven to be particularly effective

Soft soap (€ 17.27 at Amazon *) and alcohol
garlic
Bracken
and nettle

exposed.

Soft soap and alcohol

Youtube

A spray made from liquid soft soap and denatured alcohol is almost a classic in the fight against mealybugs and other pests. This home remedy is very effective, but it is not suitable for all plants. Therefore, before use, carry out a compatibility test in which you only apply the solution to a small area. Then wait a few hours: If the plant shows no reaction and no changes can be seen in the area, carry out the spray cure. If, on the other hand, stains or curls appear on the treated leaves, then the treatment should be avoided.

Prepare the soft soap-alcohol mixture as follows:

Stir in a tablespoon of liquid soft soap or dish soap
in some warm, lime-free water.
Add a tablespoon of denatured alcohol.
Caution: Denatured alcohol is extremely flammable! No open fire and no heat source nearby!
Dissolve everything in a liter of soft water.

Now fill the spray in a suitable spray bottle and spray the infected plants with it extensively. Do not forget the undersides of the leaves and the leaf axils - this is where the mealybugs particularly like to sit. Alternatively, you can dip a cotton swab into the solution and dab each louse individually.

Vegetable brew

For many plants, especially orchids, plant extracts based on garlic, nettle or bracken are much better tolerated. You collect the last two ingredients in nature, where both are abundant. In the case of nettles, be sure to collect leaves and stems from specimens that are about to bloom - these have the highest proportion of active ingredients.

Fight scale insects: Soap and alcohol run and nettle or wormwood manure

And that's how it works:

You need 200 grams of nettles or 100 grams of bracken or garlic.
Use whole bulbs of the garlic together with the skin.
Chop all parts of the plant as small as possible.
The better the active ingredients can be extracted.
Pour hot water over the plant material.
However, the water should no longer bubble.
Let the brew steep for about 24 hours.
Strain off the plant parts.
Fill the brew into a spray bottle.

Then use the product as a spray or water the infected plants with it. It is important that you carry out the cure several times with an interval of several days. This is the only way to catch all mealybugs, especially those freshly hatched from the eggs.

Mealybugs on the roots - what to do?

If, on the other hand, the mealybugs are sitting on or in the roots, first pot the plant out. Subsequently

remove any adhering substrate
and dispose of this
thoroughly clean the planter
and disinfect it with alcohol
rinse the roots thoroughly in the shower
and immerse them in a garlic or nettle stock for about 15 minutes

After this treatment, place the plant in fresh substrate and keep an eye on it. If the mealybugs appear again, repeat the treatment.

Digression

Which biological pesticides still help?

Biological pesticides, for example based on pyrethrum (obtained from chrysanthemums) or neem (obtained from the seeds of the Indian neem tree) reliably help against all kinds of pests, but not against mealybugs. At least that applies to externally applied agents. These do not penetrate the solid protective layer under which the insect pests sit. Instead, you can purchase special products in stores that you simply add to the water or stick into the substrate as sticks. The plant absorbs the active ingredients so that they get into the sap - and thus attack the mealybugs from the inside.

Use beneficial insects to combat mealybugs and mealybugs - naturally

Beneficial insects - useful because they are predatory insects - have proven to be very effective in combating mealybugs and other pests. But be careful: you must not use them together with pesticides (not even based on neem, etc.!), Because the beneficial insects are also killed by them. Help against mealybugs:

Ladybug
Lacewing
Parasitic wasps
Hoverflies
Predatory beetle

You can get the natural predators of mealybugs in specialist shops, where the animals are offered as larvae. Use them in accordance with the instructions on the package, paying particular attention to the recommended temperature and light conditions. This is the only way for the beneficial insects to develop as desired. After the treatment, the insects will disappear on their own.

In the garden you should pay attention to a healthy ecological balance, in which useful insects and other animal helpers such as bees, bumblebees, butterflies, birds and hedgehogs feel comfortable. This way you keep the pests at bay in the first place. Cultivate many umbelliferous plants, as these are among the beneficial plants' preferred food plants - usually only their larvae feed on predatory food.

Digression

Never scrape off mealybugs!

Often one reads the “tip” to simply scrape off the mealybugs and mealybugs and remove them that way, at least with a low infestation. Better not do that, because under the protective layer are not only the actual louse but also its eggs and young larvae. If you scratch the layer, all you have to do is kill the adult louse - but you will spread their tiny eggs and larvae on without being noticed. As a result, the animals continue to multiply happily.

Effectively prevent mealybugs - the pests don't stand a chance

These preventive measures make sense to prevent an infestation with mealybugs or other pests in the first place:

Pay attention to optimal location conditions for each plant.
Avoid over- or under-supply with water.
Avoid over- or under-supply with fertilizer.
In particular, nitrogen-based fertilization weakens the plants.
For indoor plants, keep the humidity high.
Hibernate them - depending on the species and variety - as cool and light as possible.

In the case of garden plants, you can ensure a strengthening of the plant's immune system by regularly spraying or watering with nettle or field horsetail brew. You should also avoid monocultures, as they encourage pest infestation. Plant neighbors such as lavender, nasturtiums, savory, garlic, onions, leeks (ornamental leek) and chervil keep many pests away.

frequently asked Questions

Are mealybugs also dangerous for humans?

Don't worry, mealybugs are not dangerous to humans or pets. The pests feed exclusively on nutritious plant saps, which is why only garden and indoor plants are at risk.

Where do the mealybugs come from anyway?

In most cases, you drag the pests home with newly purchased or gifted plants. Well-hidden individual specimens are not even noticeable when selecting, and plants that are slightly infected often still look very healthy. If the conditions are right at home, however, the plant lice multiply explosively. A dry, warm room climate is particularly beneficial for their development.

When are mealybugs particularly common?

Mealybugs appear on indoor plants all year round, but you will only find them in the garden during the growing season. In winter the pests go into hibernation just like the plants, after all, no saps flow in the cold season. This is different with indoor plants, at least if you cultivate them warm all year round.

Can mealybugs tolerate the cold? Does it perhaps help to put the infested house plants out on the balcony?

Unfortunately, mealybugs and scale insects are quite insensitive to climatic changes. They occur in both dry and humid indoor air and can even tolerate frosty temperatures. It is therefore pointless to put infested house plants on the balcony in winter - the pests will surely survive the cold shock. Only your plants die, as most exotic species come from the tropics or subtropics and are therefore not frost hardy. During the summer months, however, it can be advantageous to put infected plants outside - this makes control easier.

Can mealybugs actually fly?

In fact, mealybugs can fly, usually only males. Outwardly they resemble the whitefly, so that confusion is sometimes possible. The male mealybugs and mealybugs die after mating, while the females build a protective cocoon and thus become immobile. But be careful: These pests can reproduce in their first generation, fertilization is not necessary!