Be informed about the pest. Remove places where pests may lurk such as debris or piles of wood. Reduce weed growth which may attract pests by weeding and applying mulch between plants. Garden with pest-resistant native plants that have evolved alongside native insects and provide habitat for wildlife.
Remove insects by brushing them away, putting out traps (for slugs), creating prickly barrier using crushed eggshells or oyster shells, crushing by hand, or using a forceful spray of water.
Avoid overhead sprinkling in the evening, a major cause of mildew on sensitive plants.