These tiny mites are difficult to see with the naked eye. They are devastating to a wide variety of plants. The first sign that your plant may have Spider Mite is speckling on the leaves, followed by distorted leaves and stunted growth. In the case of a severe infestation, webbing may appear. Spider Mites prefer it hot and dry, so it is important to raise the humidity around the plant.
They are a very small insect that leave silvery brown ‘dry’ patches on the leaves with black dots. The adults are tan and dark with wings and are difficult to spot due to the fact that they ‘flick’ off easily. They deposit their eggs on young leaves and in flower buds and this can lead to shoot tips and flower buds becoming distorted if they have been damaged by the insects feeding.
Aphids – of which the most well-known is greenfly – are small sap-sucking insects that can be green, peach, black or almost see-through. Often the first sign that a plant has greenfly or aphids is the appearance of white shells that these insects shed at each stage of their development. They produce a sticky waste called ‘Honeydew’ which quickly develops a black sooty mould that coats the leaves. This will lead to new growth being distorted or stunted.
Most species are black in colour and are very small (less than 1.5mm), although a few species may reach up to 7mm long. Their key identifying features are long legs and long thin wings. They lay their eggs in the root zone, the larvae hatch and then they eat the plant roots.
These insects are kite-shaped ‘white’ flies, which means they are easy to see on green leaves, but difficult to catch as they fly off. Whiteflies can leave a sooty mould on the leaves which can lead to distorted and stunted growth. In addition, they also carry fungus and disease.