Fine webbing on plants

Fine, silky webbing on the leaf undersides and between shoots, especially with tiny pale stippling on the blade, indicates spider mites. These are minute mites (under 0.5 mm) that suck sap, causing leaves to look dull, yellow and dry out. They multiply rapidly in warm, dry air, for example near radiators.

Typical signs are fine, pale stippling (feeding punctures) on the upper leaf surface and delicate webbing underneath and at shoot tips. The mites themselves are barely visible – the easiest test is to tap a leaf over white paper and watch for moving dots. Heavy infestation leaves silvery-brown, drying foliage.

Raise the air humidity and mist the leaves with water regularly, since spider mites dislike moisture. Remove heavily infested leaves and treat the plant with a miticide (acaricide), oil or soft-soap solution, covering the leaf undersides. Repeat every few days to catch newly hatching generations.