Indoors this nasty pest can be present all year round, as temperatures and hours of daylight rise you may find bigger infestations and problems outdoors.
You can treat scale with nematodes, solution is sprayed on to the leaves of affected plants. The nematodes 'swim' on the film of water allowing them to enter the scale insect and kill them.
The temperature must be above 14°C for treatment to work and you must follow the steps below carefully but this provides a really great way of controlling scale.
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You would be forgiven for mistaking scale insect and the evidence of it's presence as aphid as they suck the sap from your plant and produce large quantities of honeydew. Some species' eggs are covered in white waxy masses leading gardeners to believe they have mealybug or wooly aphid.
As their name suggests, they look like scales and form on the stems of plants and on the underside of leaves, especially on the veins.
They start off light brown and weaken plants through their feeding but also by stopping the plant from being able to photosynthesise due to the black soot that eventually covers the honeydew.