Thrips are minute, slender, winged insects which feed on the undersides of the leaves, on young stems and on flowers by scraping the surface tissues and sucking up the sap. Attacked leaves show a characteristic fine yellow or silvery mottling. Feeding areas on the flowers show up as white flecks. Severe infestations can lead to the plant growth becoming puckered and distorted. The plants are frirther disfigured by small blobs of liquid excreted by the insects and these often become covered with a brown mould. Attacked plants tend to become stunted and may lose their leaves. Young shoots may be distorted whilst attacked flowers are malformed and may fail to open fully.
Many types of houseplants are liable to be attacked, including chrysanthemums, cineraria, cyclamen and fuchsia.
Thrips are readily controlled by general insecticides.