Ladybugs (family Coccinellidae) are widely recognized as beneficial insects in natural ecosystems and managed landscapes. These beetles are highly valued for their predatory habits, making them a natural form of pest management for gardeners and farmers. Understanding what draws ladybugs to an area—a combination of food sources, supplemental nutrition, and safe harbor—is the basis for attracting and retaining them.
The Lure of Prey
The primary attractant for ladybugs is the presence of soft-bodied insect prey, which serves as their main food source and is necessary for reproduction. Ladybugs, both in their adult and larval stages, are voracious predators with an appetite for pests like aphids, scale insects, mealybugs, and whiteflies. They are not simply drawn to the plants themselves, but rather to the areas where these pest populations are active.
Ladybugs locate their prey by detecting specific chemical cues, including the pheromones emitted by the pests and the volatile compounds released by plants under insect attack. A single adult ladybug can consume several hundred aphids before laying eggs, and the larvae are even more efficient, with some species consuming up to 5,000 aphids during their development. Female ladybugs require this protein-rich diet to produce viable eggs, and they will only lay eggs where the prey density is high enough to sustain their offspring.
Supplemental Plant Resources
While soft-bodied pests are their main food, ladybugs also rely on plant-based resources, such as nectar and pollen, particularly when prey is scarce. These supplemental food sources provide carbohydrates and other nutrients that help sustain the adult beetles between feeding events. Plants with small, accessible flowers are effective because they allow the ladybugs’ small mouthparts to easily reach the pollen and nectar.
Specific plants, like dill, fennel, yarrow, and cosmos, are known to be strong attractants due to their easy-access flower structures. Herbs in the carrot family, such as dill and cilantro, often produce umbel-shaped flower heads that act as accessible landing pads, offering abundant pollen and nectar. Letting certain herbs and flowers, like dandelions or sweet alyssum, go to bloom ensures a steady supply of these resources throughout the season. Beyond nutrition, these plants also provide physical structure, offering sheltered surfaces on the undersides of leaves where ladybugs can deposit their eggs.
Providing Necessary Shelter and Water
For ladybugs to remain in an area long-term, they require shelter and a source of water. Ladybugs need safe places to rest, seek refuge from harsh weather, and aggregate for overwintering during cold months. Ground cover, leaf litter, untreated wood, and bundles of hollow stems provide crevices and protected spaces for these insects.
Access to water is important, especially during warmer, drier periods, but ladybugs cannot drink from open pools and may drown in standing water. Providing hydration is best achieved by misting foliage, which creates small droplets that the beetles can safely consume, or by placing a shallow dish with small stones that offer a safe landing spot. Avoiding the use of broad-spectrum chemical pesticides is paramount, as these chemicals kill both pests and ladybugs, negating all efforts to attract and retain these beneficial predators.