Polytepal Daylilies

The typical single daylily has three sepals and three petals. The sepals and petals together are known as tepals. Polytepals, therefore, are flowers that contain more than the typical number of tepals. It would be easier to think of the flowers in their proper perspective if botanists had reversed the letters and referred to these flowers as "polypetaled" a term most people would easily understand. Most people first notice that these flowers have more than the typical three petals.

The daylily flower is composed of four whorls: (1) sepals, (2) petals, (3) stamens, and (4) the pistil. Normally, each whorl has a characteristic number of segments: for example, the typical daylily has three sepals and three petals. Typically two stamens are associated with each petal, one attached to the center-of the petal and the other attached to the edge, making six the usual number of stamens in the whorl. Every daylily has only one pistil, but upon close inspection you can see that it is divided into three parts. In short, the typical daylily is a three-part affair, with layers of flower parts all divisible by three.

The polytepal flower changes all this by increasing the basic number from three to four, five, or possibly even more. In cases in which the basic segments have been changed from three to four, each flower part exists in multiples of four. This results in four sepals and four petals. Since there are four petals, each with its characteristic two stamens, the flower has eight stamens instead of the usual six. The pistil also contains four chambers. It is difficult to see that the pistil has four, rather than three, chambers, but the seed pod will show it more clearly. If you pollinate the pistil, allow the flower to form a seed pod, and allow the seed pod to mature, you can clearly see that the seed pod has four seed chambers, rather than the typical three.

People often confuse polytepal daylilies with double daylilies since both contain more than the normal number of petals. Double daylilies increase the number of petals or petaloids either by adding extra whorls or layers of petals or by modifying stamens. Each whorl of petals, however, still contains three petals. And the whorl of stamens still can only produce six petaloids. Polytepals, on the other hand, do something very different. First, no petaloid tissue is added to the stamens. Second, polytepals have only one layer of petals. Instead of adding layers, they change the number of petals within the single layer.

Polytepals are not universally loved. Many hybridizers see them as the ugly ducklings of daylilies. Polytepals with four petals tend to look square, which has less of an aesthetic appeal for many people; however, we are in the infancy of this flower type. Most polytepals lack petal width and refinement, but such is typical of the early days of any breeding effort. Also, all commercially available polytepal cultivars thus far are diploid-with some exceptions, hybridizing efforts and breaks by serious hybridizers today occur at the tetraploid level. The lack of even a single readily available tetraploid polytepal has seriously hindered hybridizing efforts to date. However, several tetraploids occasionally throw polytepal blooms, and efforts are ongoing to convert diploid polytepals to tetraploid.

Many hybridizers hope to see polytepal flowers become more beautiful as modern daylily features are bred into them. One major goal is to breed fivepetalled daylilies for the round and full look that five petals can impart. Increasing petal width has been a goal among normal single-daylily hybridizers in their work towards rounder flower form-five petals would instantly give an even rounder form to the flower. With additional petals, other features such as fancy edges become more dramatic. The possibilities for polytepal daylilies still can be only imagined: polytepal doubles would exponentially increase the number of flower petals and fullness of bloom, and polytepal spiders would have more hanging tendrils, looking more and more like spiders.

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