Hi, question for the hybridizers and diploid to tetraploid converters. I have not read anything about how the conversion process might affect the appearance of a daylily variety. Does it? What tends to happen? Running across these photos today, it does look like something happened here:

First picture, "Midnight Mirror". Second picture, "Tet Midnight Mirror".





Thanks for any thoughts.

I just posted this elsewhere:
Dip (left), Tet (right):


There are some articles and threads on the subject.
I forget most of the info. But cold hardiness can improve.

Flowers can get "stiffer" as can scapes. This may be seen as a downside in cases. Patterns may potentially be lost, or change. And fertility may be reduced or destroyed depending on how well the conversion takes place, it may lose fertility one way round (pollen is OK for my tet pink stripes so pod must be the problem).
If I remember more, I will come back.

I think the conversions are mostly considered bridge plants to bring cool new features to the tet world (e.g. like tet RFK or tet Emerald Starburst did).

Here is an older post on fertility:
The thread "Do Tet Conversion Daylilies Require Special Growing Conditions?" in Daylilies forum

Old blog
https://garden.org/blogs/entry...

in the tet conversion of 'Rainbow Radiance' I have, the picture shows loss of polychrome and the color changed

Dip [registered] version of Rainbow Radiance

If you haven't read them, there is a set of Oscie Whatley presentation notes in the AHS archives on the subject of conversions that may help you.

Fertility of conversions will nearly always be less than that of the diploid versions. That applies to both pod and pollen. The fertility of normal tetraploids is on average less than the fertility of diploids. This is a side-effect of doubling the chromosomes. Although it is not avoidable (on average) it could be alleviated with time and the passage of generations of tetraploid breeding if daylily hybridizers selected the cultivars they used as parents for increased fertility (choose parents with above average fertility).

Scapes may blast on tetraploid conversions (high amounts of water may cause the scape to break if the abundant water happens at the time the scape is rapidly elongating).