Daylily Season

At this time of year, as I walk around my garden each morning, I often find myself counting the remaining buds on daylilies or feeling sad at the sight of the last flower blooming on a favorite variety. I love the daylily season, and that season is now past its peak in my garden.

Daylilies are not lilies (Lilium) at all, but flowers of the genus Hemerocallis. These Asian native flowers bear some resemblance to lilies and were once (but are no longer) classified by taxonomists as part of the larger lily family (Liliaceae). Both the common name “daylily” and the botanical name Hemerocallis (rough translation: beauty for a day) refer to one of the important ways that they differ from the true lilies, the fact that each flower opens for just one day. Because a single plant can have hundreds of buds, however, the bloom period may last for several weeks (or even longer).

Hemerocallis plants have proven relatively easy to hybridize and have attracted an ever-increasing number of both professional and amateur daylily breeders. The result has been an explosion of cultivars. The American Hemerocallis Society lists almost 70,000 named, registered varieties – and this does not even begin to account for all the daylilies out there. The AHS database does not include species plants like H. flava, H. fulva (the common orange daylily) and H. citrina. In addition, hybridizers typically name and register only a fraction of the seedlings that their efforts produce, but many of their unregistered varieties find their way into gardens and into commerce. My own garden includes unnamed seedlings from two Maine daylily breeders, a deep pink flower and a pale ruffled pink from the hybridizer Don Celler, who used to have a daylily nursery just a few miles from my house, and a vivid gold flower from the Barth breeding program.

In order to impose some kind of order on the dizzying variety of daylilies, cultivars are typically described by color, height, flower size and shape, bloom period, whether or not they go dormant during the winter, and number of chromosomes. Diploid varieties have two sets of chromosomes, one from each parent. But breeders have developed techniques to double the number of chromosomes, creating tetraploid cultivars which typically have thicker, stronger flower scapes and larger, more substantial flowers.

Daylilies are sometimes described as “perfect perennials” because of their variety of colors and flower characteristics, the wide range of climates and soil conditions in which they can be grown, the relative absence of disease and pest problems, and the fact that they play nicely with other plants in the garden. Not all varieties can be grown in all climates; but with tens of thousands (hundreds of thousands?) of cultivars available, most gardeners still have lots of choices. I have daylilies growing in every part of my garden. And while some people like to plant large drifts of a single variety, I prefer to group plants that are similar in color, but that differ in bloom time. Using this strategy, the ten different varieties of Hemerocallis growing in my blue and yellow border, for example, provide blooms from June to August.

The first daylily to bloom in my garden each year is the extra early species Hemerocallis flava, which blooms in June with the Siberian irises. Because this variety finishes blooming before any of the others begin, I don’t consider it part of daylily season but more of a preview. Daylily season begins in earnest in late June or early July when the early rebloomers, ‘Boothbay Harbor Gold’ and ‘Happy Returns’ open their first flowers. Within a week after these two plants have begun to bloom, each is boasting multiple flowers every day, 6-8 additional daylily varieties are blooming in my garden, and two dozen other varieties have begun to bud. At the height of daylily season in late July, I can have as many as thirty different varieties blooming simultaneously.

To see a slide show of daylilies in my garden – including identifying information – click on the collage above.

xx

The first daylilies I grew in my garden were all relatively early season bloomers. Over the years, as I have added more daylilies, I have selected varieties to extend the daylily season. When I planted the fence border two years ago, I chose several very late cultivars that bloom well into September. So even as the display of yellow daylilies in the blue and yellow border is winding down and the late blooming ‘Orange Bounty’ is opening its last flowers, ‘Final Touch’ and ‘Autumn Minaret’ have just opened their first flowers, and ‘Sandra Elizabeth’ has just begun to send up flower scapes that promise more days of beauty to come. Daylily season may be past peak, but it won’t end in my garden until frost.