Ultimately, the solution to the mite problem and the pest problem in general is to prevent the garden from becoming infected. Following certain simple rules will help:
Wear freshly washed clothes or change into a garden outfit when going into the garden.
Never work outdoors, especially in a garden or other vegetative or turf area right before working in your indoor garden.
Pests are frequently carried in on shoes. Do like Mr. Rogers and change your footwear before you enter the garden.
Don't use outdoor soil, tools or containers in the indoor garden
If a plant is to be introduced to the garden, first do a close examination and then put it in quarantine for five or six days. Examine it closely, especially the underside of leaves, before placing it in the garden.
Close up any unfiltered airways or holes through which plant pests might enter. Make sure that air intake from outside is filtered.