Strong increase in biological pest control in ornamental plant cultivation

Commercial growers of flowers and ornamental plants in the Netherlands are increasingly using biological pest control. In 2008 this form of pest control was used on no less than 80 percent of the total area of roses grown in glasshouses.

Predators fight infestations

Biological pest control can be applied to a number of common infestations such as thrips, red spider mite, white fly and aphids. Plant growers use predatory mites, ichneumon wasps or ladybirds to control these pests. The number of species used for this purpose is increasing. In 2008 over 25 species of antagonists were used for flowers and plants grown in glasshouses. In 2000 this was still only 15 species.

Biological pest control was already used on 80 percent of the area of roses grown under glass in 2008. In 2000 this was still only 50 percent. The use of chemical pesticides per hectare of roses fell by nearly 40 percent .

Growers of flowering potted plants were already using biological pest control on 50 percent of the cultivated area in 2008, for flowers grown in glasshouses it was used on just over 46 percent of the 1,730 ha used to grow these flowers. Per hectare, the use of chemical pesticides on flowers was reduced by nearly 35 percent.

Biological pest control in greenhouse ornamental plant cultivation

Predatory mites against red spider mite

Although chemical pesticides can be used against red spider mite, infestations with these mites are often controlled biologically using the predatory mite Phytoseiulus persimilis. In 2008, this predatory mite was used on nearly 30 percent of the area of flowers grown under glass; for gerberas and roses it was even used on 66 and 76 percent of the areas respectively. Growers of potted plants use biological pest control on just over 10 percent of the cultivated area. 

Predatory mites against red spider mite in glasshouse ornamental plant cultivation

In the cultivation of vegetables under glass, biological pest control is used for nearly the entire cultivated area, more than 3,400 ha in 2008, although the use of biological antagonists on cucumber plants fell to 90 percent of the total area. The use of chemical pesticides by vegetable growers has been reduced by more than 30 percent per hectare.

Biological pest control in greenhouse vegetable cultivation

Rob Vijftigschild