With their pristine trumpet-shaped white blooms and bright red stamens, Casablanca lilies will add elegance and charm to the flower bed from early June until August. With widths of 10 to 12 inches on stems up to 4 feet tall, the big, sweet-smelling blooms are impossible to miss. Like all oriental lilies, Casablanca lilies aren't fussy and are surprisingly trouble-free–in spite of their spectacular beauty. Plant Casablanca lilies in spring or fall.
Spade the soil to a depth of 12 inches, then work in 3 to 4 inches of an organic material such as compost, manure or dry leaves. Casablanca lilies should be planted in well-drained soil and full sunlight.
Dig a hole for each bulb, allowing 8 to 12 inches between each bulb. Plant each bulb approximately three times deeper than the height of the bulb.
Fertilize the lilies when growth emerges in early spring using a slow release fertilizer or a low-phosphorus granular fertilizer with a ratio of 5-10-10. Read the directions on the container for specific amounts.
Keep the lilies constantly moist. Allow a hose to run slowly near the plant until the soil is wet 6 inches deep. Avoid wetting the foliage.
Pinch off (deadhead) lily blooms as they wilt so the plant will continue blooming and won't expend energy on going to seed too early. Allow the foliage to remain on the plant until it wilts and dies.
Spread 4 to 6 inches of pine needles, straw, leaves, or other organic material to protect the plant from changes in temperature. Remove the mulch when the shoots emerge in spring.