Why Test Daylilies?
Angelo Cerchione, Executive Director of the All-American Daylily Selection Council (AADSC) asks rhetorically. Why? Because all daylilies are not created equal. Since the turn of the century, over 1,000 hybridizers have named, registered and introduced over 42,000 daylily varieties – virtually all of which are described in catalogs as “beautiful”. Yes, we agree; the blooms are beautiful but how does the rest of the plant perform?
The question is an important one because of those 42,000 varieties, 13,000 are still in commercial circulation. In fact, the confusion over performance is so great among growers that as late as ten years ago they largely avoided this species. Wide-scale testing, an awards program, and earned publicity during the last six years has made the daylily today the number one flowering perennial in the United States.
Since we began, we’ve screened and tested over 6,000 daylilies. Based on our results thus far, we can reasonably predict that of the 13,000 cultivars in broad service, 12,000 would fail our commercial criteria completely, 800 would be rated “Good” and perhaps 200 would test out as “Excellent”.
We test a daylily for 52 performance characteristics at test sites that range from USDA Hardiness Zone 10 in Florida and California to Zone 2 in Alberta, Canada. Here’s what we’ve learned in the last 12 years. The average daylily tested will give you two to three weeks of bloom; top performers, on the other hand, will range from 90 days in Zone 4 to nearly 300 days in Zone 9. This is our advice to growers and buyers alike. “Look for a daylily that will bloom for 60% to 90% of the overall bloom period (i.e., your entire summer plus some) for all perennials in your garden.”
Our second strongest concern is foliage performance. Once the bloom goes off, will you still have an attractive ground cover? In Zone 6, for example, in North Carolina, Tennessee, etc., average foliage tends to remain at its best for six weeks. Our test program looks at foliage color and density when rating this performance characteristic. Top-notch daylilies will give you 18 weeks of super-looking foliage – a bit shorter in the north, much longer in the south. It’s the difference between a beautifully manicured and a ratty-looking garden.
You might ask, “How will the gardener know all of these things that it took AADSC eleven years to discover?” Here’s a simple guide to the most important performance characteristics. It is based on what AADSC calls its “drop dead” criteria.
Check buds – If the plant before you only has one or two bloom-carrying stalks (“scapes”), pick the one that shows at least 15-20 buds per scape. If some of the bloom has already gone off, the scape will show countable scars where the buds had been attached. Some daylilies send up lots of scapes. These are “repeat” bloomers. If you see signs of heavy past or present scape-making, then be content with smaller numbers of buds
Check foliage color – Look for a rich green or blue-green foliage. If the foliage color is right, the plant will continue to be a rich garden asset with or without bloom. Paler fern green foliage may be suitable in areas with light shade.
Check foliage density – A simple test. Look straight down into the pot and then take that daylily whose foliage will not allow you to see the fill material below. Early indications of foliage density spotted this way will tell you whether your garden will achieve a finished look in one full season or three.
Check existing bloom – Shop for daylilies in the afternoon on a hot day. Many daylilies are not sun-fast. Some will look as though half the daylily bloom was dipped in bleach by 10:00 am. It’s terribly unsightly. In addition, some of the darker colored daylilies will “slick” — the surface cells holding the pigment will change in color and often drip off. As a general rule, this second problem can be minimized by planting dark purples and reds in shadier areas of the garden.
Check spent bloom – If deadheading is not your thing, look for the “self-cleaning” daylily. Once the bloom goes off, the best daylilies roll their flowers into little cigarette-shaped spents. Unassisted, a self-cleaner will lose these in two days. Some daylilies will retain their spent for a week. Look at the flowers before you and tap the spents with your finger. If they drop off easily, you have a winner.
Check scape and foliage heights – The ideal is a scape that carries the bloom at least an inch or two above the general mass of the foliage. If this is not evident in the plants before you, your bloom will be hidden inside the foliage.
Once you’ve found a daylily that meets this test and your personal definition of beauty, here are some other things to consider. Beyond the need for beauty, the daylily can solve a lot of problems facing gardeners. In point of fact, we think of the daylily as the “Swiss Army knife of the plant kingdom”.
Have steep banks that nothing else will grow on? We’ve reclaimed banks with 70 degree slopes that defied crown vetch.
Suffering from ocean spray, occasional salt water inundation or run-off from trucks spreading road salt in winter? Daylilies are salt tolerant. Coastal Gardening with Daylilies
Do you have areas in your garden in which erosion is rampant? The root system of the daylily forms a huge chain mail-like mat beneath the surface.
Live in fire-prone areas? Daylilies are engorged with water and when planted in mass can stop a brush fire in its tracks.
Are you seeking a plant that requires very little maintenance? For the North Carolina Department of Transportation, the daylily has become their acknowledged “plant of choice”. In fact, recent studies have shown that it is cheaper to use perennials as a soil-stabilizing mechanism along roadsides than to use grass. North Carolina has already converted over 2,500 acres of roadsides into linear gardens.
And if that’s not enough, the next time you have sweet and sour soup at your favorite Chinese restaurant, be aware that the ingredient called “Gum Jum” or “Golden Needles” is actually the buds of the daylily. Practically all of the daylily is edible and is higher in protein and Vitamin C than most of the vegetables in popular use.
And let’s not forget beauty! In our performance verification testing, we have found 28 different but distinct patterns in the face of the blooms. The flowers range in size from one inch to ten. Some will have over 100 blooms per scape. The blooms come in most every color except a true black and a true blue. Usually, the bloom consists of six petals (actually three sepals and three petals), but there are doubles (those with over 14 petals) that look like peonies, and “spiders” with enormously slender petals. Plant foliage will range in width from 12 to 60 inch clumps, and in height from 9 to 40 inches, with scapes soaring to six feet.
What’s really amazing is that most of the daylilies in long supply today are 30 to 50 years old and, from what we’ve seen so far, they were not necessarily the best daylilies in their own time.
Why test? To avoid disappointments, and to benefit from all of the attributes of America’s favorite perennial.