Use of biological control agents and chemical pesticides in greenhouses in 2015

Statistics Norway conducted its third survey on the use of biological control agents and chemical pesticides in greenhouses in 2015. The survey comprised the following crops: flowering potted plants, cut flowers, bedding plants and decorative plants, lettuce, herbs, tomatoes and cucumbers.

The voluntary sample survey comprised a gross sample of 405 greenhouse holdings, and had a response rate of 87 per cent. However, the response rate varied significantly by crop, from 97 for herbs to 85 for ornamental plants.

Biological control agents were applied on 31 per cent of the area of ornamental crops grown, and 90 per cent of the area of edible crops. The proportion of flowering potted plant area treated with biological control agents was 56 per cent, while the corresponding proportion of decorative plants, cut flowers and bedding plants was 37, 20 and 15 per cent respectively. In the edible crops, i.e. cucumbers, herbs, tomatoes and lettuces, 96, 94, 92 and 66 per cent of the crop area respectively was treated with biological control agents. 

Treatments against aphids accounted for the largest percentage of accumulated areas of biological control agents in flowering potted plants, decorative plants, lettuce and herbs, while treatments against thrips were most common in areas of cut flowers, bedding plants and cucumbers. Treatments against whitefly accounted for the largest proportion of accumulated areas of biological control agents in tomatoes.

The extent of chemical pesticide usage varied by type of crop. Ornamental crops comprised 83 per cent of the area treated with pesticides at least once, while edible crops accounted for 33 per cent. The proportion of flowering potted plants area treated with chemical pesticides at least once was 90 per cent, while the corresponding figures for bedding plants, decorative plants and cut flowers were 82, 64 and 54 per cent respectively. Fifty-three per cent of the cucumber area was treated at least once chemically, compared with 50 per cent of the lettuce area and 13 per cent of the tomato area. Only about 2 per cent of the area of herbs was treated chemically. 

Growth regulators accounted for almost 47 per cent of the total pesticide treated area of ornamental crops, insecticides 43 per cent and fungicides almost 10 per cent. In edible crops, fungicides accounted for almost 63 per cent and insecticides for 37 per cent of the accumulated area treated with pesticides. Insecticides were the most important control agents on areas of tomatoes and lettuce, while fungicides were the major group used on cucumbers.