Grow in full sun with some shade in late afternoon. Too much shade can make lilies leggy, "stretching" for the sun. Soil must be well-drained, with added compost or peat moss. Top dress in fall with mulch to avoid "heaving" from early winter thaws. Keep soil cool in summer with over-plantings of ground covers or annuals. Plant 2 to 3 times as deep as their diameter.
Regales are funnel-shaped and will tower over perennials catching the eye upward. Plant in masses.
Lilies have few problems. Aphids can attach to buds; treat with mild insecticidal soap since aphids can carry a mosaic virus which has no cure. Plants must be removed from the site. Mosaic causes yellow streaking or mottling on leaves, disfiguring buds and flowers. If planted in hot and humid areas it's best to keep lilies in raised beds to avoid fungal problems. Some rodents (such as mice, voles, gophers and chipmunks) like to eat the bulbs. If these are problems in your area, plant bulbs in wire mesh cages or buried pots. Deer and rabbits eat leaves, buds and flowers. Regal lilies require staking since they can grow up to 6'. If used for cutting always leave at least 1/3 of the stalk for nutrition for the following year's development.
Plant in groups integrated in a perennial border. Planting together different species of lilies (Asiatic, Oriental, trumpet, etc.) will allow for a full season of blooming lilies. Plant perennials near lilies to cover left over greenery after flowering.