Apply biocontrols
Most houseplant pests, including red spider mites, aphids and mealy bugs, can be kept at bay using natural predators. These are known as biological controls, and there’s a different one for each pest. As they are living creatures, they have to be introduced when conditions are right for them to be active. This is usually when the temperature is a little higher than the pest needs to wake up and feed, to ensure the biocontrol predator has plenty to eat. Biological controls are sold by mail order, as they won’t keep on a shop shelf. Read the instructions and follow them to the letter.