Horticultural (soft) soap
This product is a highly refined soap made from natural oils which acts as a contact insecticide with no residual effects once it has dried. Ideal to use before the introduction of biological controls, perhaps while waiting for the residue of previous chemical sprays to dissipate.
Soft Soap Concentrate reduces population and the breeding capabilities of Aphids, Whiteflies, Red Spider Mites, Thrips, Mealybug and Scale . It comes in a 250ml bottle which dilutes into up to 12.5 litres of solution which can either be used in your spray gun, or applied with a sponge.
Warning: There are certain plants which can be damaged by Soft Soap - these include Fuchsia, ferns and bedding plants in bloom. Test a one or two leaves first if you are in doubt. And use the correct dilution - one part liquid to 30 parts water for strong leaves such as bays and camellias, but one part liquid to 50 parts of water for softer leaves such as peppers.