Culture
Easily grown in average, medium moisture, well-drained soils in full sun to part shade. Daylilies perform well in a wide range of soils, but prefer deep, fertile loams. Deadhead spent flowers daily for neatness and remove scapes when flowers have completed bloom. Plants are tolerant of summer heat and humidity, but appreciate deep watering in dry spells to keep foliage attractive. For best performance, daylilies should be divided every 3-4 years in either fall or spring (spring is best in cold winter climates such as the St. Louis area). Hybrid daylilies will not come true from seed. Winter dormant daylilies require a cold period of winter dormancy for the best display of blooms, and are not recommended for hardiness Zones 9 and above. Evergreen daylilies will retain their foliage in warmer climates, but their foliage will be damaged in areas with cold winters and can be cut back to maintain a clean look.
Noteworthy Characteristics
Hemerocallis is a genus of about 15 species of herbaceous perennials commonly known as daylilies. These plants are native to Asia and central Europe. Most plants are fibrous rooted, but some are tuberous rooted. Daylilies sold in commerce today are almost entirely hybrids. Few straight species plants are now found in gardens. Hybridizers have expended considerable effort over the years creating new daylilies featuring flowers with new colors, color combinations, shapes and patterns. More than 60,000 cultivars have now been registered by the American Hemerocallis Society with the numbers continuing to climb. Each flower typically remains open for one (but sometime two) days, hence the common name of daylily. Flowers are produced in succession in such quantity that the plants remain in flower over a long period of time. Flowers are typically funnel-shaped to bell-shaped, often coming in a variety of different forms, including single, double, polypetalous, spider or unusual (includes crispate, cascading and spatulate). Each flower has six spreading, recurved or sometimes nearly erect perianth segments, six stamens and a long slender style ending in a small stigma. Flowers now come in almost every imaginable color except blue, often sporting such features as contrasting eyes or mid-rib stripes or a sprinkling of diamond, ruby or gold dust. Flowers range in size from 3-8” across. Some flowers have ruffled edges. Flowers bloom on naked scapes from spring to late summer. Some cultivars will rebloom. Each plant features basal, linear, grass-like to sword-shaped foliage. Cultivars may grow from 1-6’ tall, but most mature to about 3-4’. Plant foliage usually dies in fall, but is sometimes semi-evergreen or evergreen.
Genus name comes from the Greek words hemera meaning day and kallos meaning beauty as each flower lasts but one day.
'Chablis Blanc' is a tetraploid cultivar which features 6" diameter, cream flowers with green throats. Flowers appear on naked stems (scapes) which typically rise to 30" tall above a clump of arching, linear, blade-like leaves. Individual flowers open for one day. Fragrant. Blooms in early mid-season with a repeat bloom. Munson, R.W. 1980.
Problems
Daylilies are extremely adaptable perennials. They are easy to grow and relatively pest free. Mites, aphids and thrips may appear occasionally. Daylily rust can be problematic in some areas. Rabbits tend to avoid daylilies.
Uses
Easy-to-grow herbaceous perennials for gardens. Borders. Edging. Mass over large areas or grow in clumps. Dwarf cultivars are excellent in rock gardens.