In advance: You can find a selection of biological plant protection products, which are tested and used by ourselves, here.

The best tips against pests of houseplants:

• Strong and healthy plants are less susceptible.
• Moderately high humidity counteracts pests.
• As an immediate measure showering plants temporarily removes pests.
• For many pests, a neem oil-based spray is sufficient.
• A systemic insecticide works best against pests with shells (such as mealybugs).
• Against fungus gnats helps less watering or watering from below, better soil or Neudorff mosquito repellent.

In general, healthy plants that are properly watered, stand in a good substrate and get plenty of light are more resistant to all kinds of pests. A plant has natural defenses and pests always look for the easiest target. But even in the most ideal conditions there are pests, after all, even all botanical gardens and nurseries have to fight with them, in almost perfect conditions.

There are several ways to get rid of pests.

1. One opts for a chemical-free method and showers the pests with water. But this must be repeated over and over again and usually only helps in the long term if the plants are outside or the infestation was very light. In addition, pests such as mealybugs, which are very firmly attached to the plant, are difficult to remove. Diluting dishwashing liquid and spraying it on the plant is not recommended. It may help against pests in the short term, but it will also weaken the plant's defenses and the pests will be back quickly.
2. For "simple" pests, it is enough to use a neem oil-based spray. This helps especially with pests without armor, such as spider mites, thrips or aphids. However, it must be repeated several times until the pests disappear.
3. You can also use a systemic insecticide (as sticks, watering concentrate or spray). It is absorbed by the plants through the roots or leaves, and thus absorbed by the pests. This remedy works much better on pests with armor, as neem oil has little effect on them. Pests with armor are scale insects, mealybugs or root aphids. The agent lasts only a few months before it must be reapplied.

It is best to use all three methods. If you see an infested plant, bring it into the shower, let it dry and then spray it from all sides. Then use a neem oil based spray and finally the systemic agent as a stick (which takes some time to work).

Another tip: You can also dab armored pests with alcohol.

fungus gnats

An easy pest to avoid is the fungus gnat. This lays its eggs/larvae in the upper layers of soil in the pot, which can then damage the roots. However, in adult plants, there must be a severe infestation for the plant to be damaged at all. First and foremost, fungus gnats are annoying!

If you always let the soil surface dry out, the larvae will not survive and the fungus gnat will not lay its eggs there. A good soil mixture that can dry well is also important, see the topic substrate. In addition, you should use yellow stickers or transparent window stickers to reduce the number of adult fungus gnats.

Here is another tip that is very little known: Neudorff mosquito repellent contains a bacterium that kills mosquito larvae, including those of fungus gnats. You take half a tablet per 12 liters, since most watering cans hold about one liter, so a small portion of a tablet is enough. Attention: Do not touch the eyes!

Beneficial insects like nematodes

Even pests have their own enemies. Botanical gardens and nurseries use such beneficial insects to control pests. Nematodes act similarly to Neudorff mosquito repellent, but regular use is very expensive.

We regularly release predatory mites in the store to prevent pests. So if it ever crawls in the soil, it may be a beneficial insect. However, certain conditions (such as high humidity and suitable temperature) must prevail for beneficial insects and they sometimes run away through the window... 😉