Plant Pests

Plant pests are animals, plants, bacteria and viruses that damage plants through their behaviour or characteristics. Even from this list alone, it's clear that plant pests form an unmanageably large and varied group.

Most of them perform both harmful and beneficial functions within the ecological system and only become a nuisance once this balance is upset and the "troublemakers" suddenly appear in large numbers.

For this reason, it is often not at all easy to take the right action against pests, since the first step must be to establish the cause rather than reaching straight for a pesticide.

Most of the damage takes the form of feeding or sucking injury to all parts of the plant, caused by insects, mites, molluscs or nematodes. In the worst case, viruses can also be transmitted in the process, and these then represent the truly serious pests.

Viruses and bacteria often cause rot, sudden dieback of individual parts, as well as tumour-like growths or malformations on the plants, frequently resulting in the rapid death of the whole plant. There are no chemical sprays effective against these pests.

Fungi, on the other hand, often use plants as a host. They grow into the plant and draw nutrients from it. Vigorous fungal spread is usually associated with high humidity and warmth, which is why it is often a particular problem in the greenhouse.