Lilies commonly flower from spring to fall, matching most butterfly activity patterns. The colorful insects need mild temperatures and ample sunlight to warm their cold-blooded bodies for successful flight; winter is too cold for butterfly flight in most regions. With lily flowers displaying bright colors, butterflies spot them easily from the sky. If you plant multiple lilies in your garden, butterflies can conserve their flying energy and collect more nectar for sustenance. They have a relatively short lifespan to mate and reproduce before cold weather arrives.
Much like butterflies, hummingbirds are initially attracted to lily flowers' color, especially if they have a red hue. These birds have limited color recognition for other hues. Because hummingbirds hover easily above the flowers, they quickly access the nectar as their bodies brush against the outstretched stamens. Even if a hummingbird drinks from only one flower, the bird pollinates the flower with its own pollen.
Six petals splay outward as the centralized reproductive parts of a lily flower protrude into the air. A slight fragrance emanates from the flower's center point as it entices pollinators to venture closer to the flower. Because the flower has an open petal configuration, a butterfly has a chance to rest on the blossom as it feeds. That strategic stopping point allows more pollen to cover the butterfly's body. Although a hummingbird hovers, it still wants to penetrate the flower deeply with its beak for the most nectar, and so the bird get as close to the blossom's center as possible. As more pollinators visit the lilies, the pollen mixes into a genetically diverse mixture for strong seed development. (See Reference 1, 5 and personal experience)
Although lily flowers are main pollinator attractions, lily foliage also provides strategic shelter for hummingbirds and butterflies. Predators cannot find these small animals if they hide below the large lily blossoms and among the green leaves. In addition, successful lilies' surrounding soil must be moist, and butterflies and hummingbirds look for small water sources for sustenance. You can encourage more pollinators to your lily garden by adding a shallow water feature, such as a basin, for thirsty hummingbirds and butterflies. (See Reference 1 through 3)