Stella D'Oro daylilies are not true lilies. They are in the genus hemerocallis (hem-er-oh-kal'is), which is Greek for "beauty for a day". All daylily flowers last for just 24 hours before dying. Multiple flowers are produced on stalks, or scapes, with new flowers opening as old ones die. Stella D'Oro (which means "star of gold") is a dwarf daylily with plants reaching 2 feet tall (the flower scapes add another foot) and wide. These daylilies are pest (including deer) and disease resistant, making them one of the easiest daylilies to grow.
Plant Stella D'Oro daylilies in early spring or fall. Choose a spot that receives at least six hours of direct sunlight a day with well-drained, slightly acidic soil.
Work 3 to 4 inches of compost or well-rotted manure into the top 12 inches of soil at the planting site. Plant daylilies 1 to 2 inches deep, spacing them 12 to 16 inches apart.
Mulch the Stella D'Oro daylilies with 2 to 3 inches of an acidic mulch like pine straw or shredded pine bark. Wait until growth emerges and reaches 3 to 4 inches tall before mulching.
Give your Stella D'Oros 1 inch of water a week during the growing season (April through September). Give plants in fast-draining sandy soils 2 to 3 inches of water a week.
Prune off fading flowers to keep your plants flowering all summer long. Prune the flowers once a day since daylily flowers only live for 24 hours.
Top dress (fertilize) your Stella D'Oros in spring after growth appears with 1 to 2 inches of compost or well-rotted manure, bone meal and phosphorus. Apply the bone meal and phosphorus according to package directions (usually 1 to 2 tsp.).
Fertilize your Stella D'Oro daylilies every four to six weeks, after the first top dressing in spring, with a 10-10-10 or 12-12-12 commercial or organic fertilizer applied at half strength. Stop fertilizing in August.
Divide your Stella D'Oro daylilies every three to four years. Divide in early spring after foliage emerges or in early fall after flowering stops. Dig up your daylily, getting as much of the roots as possible. Break apart the clump by hand, making sure each smaller clump has two to three leaves (also called stems or fans). Cut the foliage back to 5 to 6 inches and replant in prepared soil (see step 2).
Leave the foliage intact over the winter. Mulch with 4 to 5 inches of straw or shredded leaves after the first hard frost.
Remove the winter mulch in early spring after all threat of frost has passed. Remove the dead foliage and last year's pine straw or shredded pine bark mulch. Re-apply mulch after new growth has emerged.