Place screens or fine-mesh netting around the plants to keep insects at bay. Water and sunlight will still get through and nurture the plants but parasitic bugs are blocked.
Treat the plants with a pesticide that won't harm the plant itself. Read the packaging to verify that the plants will be safe and to check what bugs the pesticide protects against.
Inspect the plants regularly, picking off by hand any insects that are visible. Wear protective gloves to guard against bites or stings.
Sprinkle a small amount of natural flour on the leaves of plants that are experiencing pest problems. The flour causes feeding and digestive problems for insects, preventing them from continuing to feed on the plant. Avoid flours containing salt, which damages plants. Natural flour without additives will not cause problems for the plants.