Maurice, thank you for your informative post! I do have a question. If you don't look at how the foliage "behaves" in different weather, how do you determine hardiness?

Mayo. This is a great group.

James, this year I used string loops from leftover paper tags. I had several hundred so I just took the paper off and then put them on my new ones. I do have some tags a friend gave me. She did her own from heavy string.

"If you don't look at how the foliage "behaves" in different weather, how do you determine hardiness?

Hardiness (winter) is a measure of how a plant survives cold weather. It does not need to have any relationship with how the leaves behave (and usually probably has no relationship). A daylily is hardy to my zone 4 winter weather if it survives winter in my garden. The only way one can determine whether a daylily cultivar is winter hardy is by seeing if it survives winter. Unfortunately hardiness is related to the actual low temperatures reached during particular winters and to the presence or absence of freeze thaw cycles during winter, depth of snow, and other factors. So plants cannot be labelled as being winter hardy or not as a general description - they can be labelled as being winter hardy to specific low temperatures. A cultivar could be described as being winter hardy to -5F or to -15F or to -30F, etc.

We could look at a couple of trees. A deciduous tree, such as a maple tree, loses its leaves before winter (zone 4) arrives. It will be obviously dormant during winter - dormant meaning not growing new leaves during winter. We could compare a maple tree to a spruce tree. A spruce tree does not lose its leaves (its needles) before winter. It is evergreen and it is also dormant during winter (zone 4). What a plant does with its leaves (that is, it either loses them before winter [dormant] or keeps them for several years including during one or more winters [evergreen]) does not necessarily affect whether the plant is winter hardy.

There is another category of growth rather than of foliage behaviour. Whether a daylily is deciduous or evergreen is a foliage characteristic.. Whether a daylily can become dormant or is ever-growing is a growth characteristic. A daylily that is ever-growing and tries to grow during warm spells in winter might not survive well in some locations but might survive quite well in other locations where winter is cold and there are no warm spells during the winter, etc.

Bottom line - I determine whether a daylily is winter-hardy to my zone 4 garden conditions by whether it survives. Otherwise I cannot know whether a daylily characterized/registered as dormant or whether a daylily characterized/registered as evergreen will actually survive here.

Maurice - Is there a term for high temp survival of daylilies? I have the opposite problem here .... perhaps too hot!

Maurice and others here participating on this thread ....

I have a new question. I am discovering something I've never had happen before. I have a LOT of seed pods forming on most all my daylily seedlings. I've harvested a few pods full of seeds already. I put the different crosses in paper envelopes and let them sit out to dry (in a house with the A/C on) for 3 days. When I looked at some of the dip seeds after 3 days they were shrunken and flat. Obviously not viable. What's up with that? When I removed them from the pods, they were ripe (because the pods were opening up) and had nice black, plump seeds. So far the few tet pod seeds that I have been drying out still look and feel viable. So this seems to be a problem with the dip seeds. Why are the dip seeds doing that?

Becky, try cutting one or two seeds in half and looking inside. Sometimes due to a failure along the line there is no embryo in some daylily seeds. A good seed should look like this inside:

beckygardener said: Is there a term for high temp survival of daylilies?

Sorry, I don't know of a specific term for the survival of plants at high temperatures. Usually high temperature effects on plants are described as "heat stress" or "high temperature stress" or "heat tolerance". Possibly if the high temperature does not last for very long it may be described as "heat shock".

Daylilies will have both minimum cold temperatures that they can survive without damage and maximum hot temperatures that they can survive without damage.

Arisumi, investigated daylily growth at several different temperatures. He only used one cultivar and his tests used constant day and night temperatures (which is different from natural conditions where night temperatures are usually cooler). He used the cultivar 'Purity' and constant temperatures of 55°, 65°, 75°, 85°, and 95° F. The plants growing at 95° F did not flower. The plants growing at 85°F 'blasted' most of their flowers and opened only a few poorly formed flowers. He described their scapes as weak and as only half the size of the scapes formed at 75°F. Seed set was poor at 85°F.

[The speed at which plants grow depends on the temperature. At low temperatures plants grow slowly and at higher temperatures they grow more quickly. In Arisumi's experiment the plants at the lower temperatures were unable to grow enough to flower during the test period but for example, some of the plants grown at 65°F flowered two to three weeks after the end of the experiment. That would not have been the case for the plants grown at 95°F.]

Maurice - THANK YOU for posting that info about temps and how they may affect daylilies. Are there some cultivars of daylilies that handle the heat better than others? My front bed is quite hot. It is south facing, no shade whatsoever, and is currently getting into the high 80's and low 90's. There are a lot of scapes loaded with buds on many of the seedlings out in that border bed. The blooms are opening nicely once the morning temps in the 70's heat up. Seems they like the heat to fully open in. Maybe 95 is the cut-off heat tolerant temp for good blooms? I also have numerous pods set on many of the seedlings. Whether those pods produce viable seeds is yet to be determined.

Also, is it possible for daylilies to adjust to temps to survive? I ask because I have actually purchased some named daylilies (not very many) that came from northern states. They are struggling in the Florida heat. I lost one last year and I am sure it was the heat factor. None are dormants. I have the best luck with seedlings grown from seeds in my garden. It's like they adapt from germination onward ....

Sue - How in the world do you cut a tiny seed like that? I don't have the tools or a microscope, but I fully understand what you are saying. Can seeds die? That is what I am wondering or were all those seed not viable to begin with? I just collected 10 more seeds from another Dip. The seeds "look" viable at this time:

Also, I was told about a VERY helpful article about hybridizing. I knew there were some articles out there, I just had to find them. This one is from the AHS library:
http://www.daylilies.org/Whatl...

I highly recommend it!!!

beckygardener said:Sue - How in the world do you cut a tiny seed like that?

Very carefully As seeds go, daylily seeds are quite big. I steadied the seed with a fingernail and cut it in half - I guess having a scalpel helped but you could presumably do it with a box cutter/exacto knife or whatever they are called (but be very careful if you try, not worth risking a nasty cut yourself).

One of the seeds in your picture looks like it has rotted?

beckygardener said:I don't have the tools or a microscope,

You don't need a microscope if you have a digital camera that can do macros. You simply take a picture as close as you can focus and then it is magnified when you look at it on the computer. If your camera doesn't do good macros then taking a picture through an ordinary magnifying glass is another possibility.

beckygardener said: Can seeds die?

Yes, or they can be non-viable from the start. Some that I've cut open just had mush where the embryo should be. Some shriveled flattish looking daylily seeds are still viable, depends just how flat they are. The floaters or sinkers test is also not reliable. What you could do is put a couple of suspects in household strength hydrogen peroxide diluted with water to 1:5 or thereabouts and give them a several days in the solution to see if there is any sign of germination.

Sue - Thank you!!

How about shrinkage. If they shrink down to a small percentage of what they were when collected from the pod, would that be another indicator of a non-viable seed? I know the ones I tossed in the trash could not possibly be viable. They are almost flat, very, very small, and completely shriveled. Is drying them out for 3 days possibly too long? I had read in the article above that you leave them out for about a day and then bag, tag, and put them in the fridge. Is 3 days too long for them to dry in an A/C environment? I am wondering if I had refrigerated them after 1 day instead waiting 3 days for drying if they might still be viable. Which is why I asked if they can die if the drying process is too long?

I also was just enlightened by the Whatley article. I have limited space to grow daylilies on my residential lot. In his article, he mentioned growing seeds/young seedlings 4" apart in rows that are 5" apart. Mine have a lot more space around them than that! Is that really possible AND practical to grow them that close?

Though in looking at my garden, I may have done something very similar to that in my newest daylily bed. Nice, neat rows that are fairly close together. It sure makes figuring out what is what in that particular bed much easier .... as I also map each of my seedlings in my beds in addition to labeling each of them with a code. This is causing me to rethink my grow-out strategy! The hardest part for me will be the culling. I've yet to do that .... (sigh)

beckygardener said:
How about shrinkage. If they shrink down to a small percentage of what they were when collected from the pod, would that be another indicator of a non-viable seed?

It would depend how much they shrank, I guess. I remember some quite shriveled and wrinkled seeds surprising me by germinating without even plumping up but presumably there is a limit.

beckygardener said:Is drying them out for 3 days possibly too long? I had read in the article above that you leave them out for about a day and then bag, tag, and put them in the fridge.

I had a quick look at the article, I got the impression he was harvesting them and immediately bagging and refrigerating? Maybe I missed the reference to one day. Anyway, to answer the question, no three days isn't too long. In the original daylily seed germination experiments by Dr. Robert Griesbach back in the 1950's he air-dried daylily seeds for 2 to 4 weeks in one experiment and they were fine. He generally stored the seeds at room temperature in paper bags until needed for his experiments, although some for later experiments were stored at 50F to prolong storage viability. They would then have been re-hydrated and refrigerated to stratify before being started in the experiments.. Dry room temp storage may not work for you in your climate (too warm and humid which is not good for seed storage), though - he was in Chicago.

What Whatley appeared to be doing was stratifying immediately by refrigerating while the seeds were still plump from the pod. They may have contained enough internal moisture for chilling to be effective in breaking seed dormancy (if there was any). So you're probably looking at the difference between immediate stratification versus drying for longer storage prior to stratification.

Seeds and "young" seedlings of course can be grown that close together, but then when they start growing larger they have to be moved to a location with more space. If all the seeds you plant were to germinate and grow, it might put you in a jam for space! If half of them don't germinate and then half of those that do die then you would have plenty of room. It is just that when they are very small they can be grown that close together, not when then get larger!

I'm learning a lot from you all. Thank you Maurice, Sue and Becky.

Maurice and Sue - Wished I had some acorns as I would be tipping BOTH of you for sharing such terrific information and references!

Sue - So basically if seeds are viable, then letting them air dry should not kill them? I've never had that problem before. It also could be that I wasn't able to hand-pollinate those blooms until much later in the day because I work. Perhaps they pollinated, but the pollen or ovary was not viable by that time. In humans, it is called a blighted ovum. I am just surprised it created so many seeds that all withered up when I air dried them. Other seeds (mainly the tets seem to be okay so far). You are right about the article not mentioning 1 day to dry. I guess I was reading between the lines and assuming it was a day. Maybe I should try an experiment to see what happens with some of the dip seeds?

Larry - I know exactly what you are talking about. Most serious hybridizers only grow them until they bloom or they evaluate the foliage and then decide whether or not to cull them. Those that they keep are often moved to a different bed, so they create different beds for different stages of a new seedling. The article mentioned using such a close planting for the first through second year seedlings. Though I do have a few robust seedlings that have definitely outgrown their siblings and other seedlings of the same age. If I was doing regular culling, then that idea of growing them close together would be quite good. Instead, I am being sentimental and have not culled a single seedling. I guess I need to toughen up and get a bit more serious with my daylily hybridizing goals!!!!

beckygardener said:Maurice - THANK YOU for posting that info about temps and how they may affect daylilies.

You are most welcome.

Are there some cultivars of daylilies that handle the heat better than others?

Yes there will be some cultivars that handle higher temperatures better than others. Keep in mind that Arisumi used the cultivar 'Purity' in his temperature tests. Purity was registered in 1949. Since then there have been many daylily hybridizers who produced their introductions in Florida. They will, either on purpose or simply by growing and hybridizing their plants in the Florida heat, have selected for daylilies that grow well and produce viable seeds in Florida temperatures. (Although if they chose to only hybridize in the cooler times of the year they may not have had strong selective pressures for heat tolerance).

Maybe 95 is the cut-off heat tolerant temp for good blooms?

Perhaps. That is best tested or looked at in locations with sufficiently high temperatures.

Also, is it possible for daylilies to adjust to temps to survive? I ask because I have actually purchased some named daylilies (not very many) that came from northern states. They are struggling in the Florida heat. I lost one last year and I am sure it was the heat factor. None are dormants. I have the best luck with seedlings grown from seeds in my garden. It's like they adapt from germination onward ....

Yes, plants can adapt to high temperatures (within limits) if those temperatures do not come suddenly. There will always be a limit to how high a temperature a particular cultivar will be able to adapt. Also different cultivars will have different rates of adapting to high temperatures and they will have different maximum temperatures. They will probably also differ in how long they can survive at high temperatures (or their seeds can develop properly, etc.).

Maurice - Survival of the fittest? Not all my seedlings survive in the heat. I have lost numerous seedlings in summer. Most though go dormant during the highest temperatures. The only thing that seems to help during those hot days is a little shade (if available) and watering. My partial-shade beds always look the best in summer. (No surprise there.) I guess it really comes down to research on cultivars and trial & error?

I have another inquiry ....

Does anyone know what program Bill Maryott uses for his daylily pedigree charts? See example:
https://daylilygarden.net/cgi-...

I did email him to inquire, but not sure if he will reply, so am wondering if anyone knows.

I must confess that I really don't understand what happens to the genetics of a tet or dip conversion. There is a possibility that the seedlings might produce the opposite if the conversion reverts back? It's a concept that seems to complicate my hybridizing because it goes beyond my scope of understanding. If the genes were to convert back, does that mean the seedling would be a sterile daylily? Sterile pollen AND pod? Or does that mean it would be "opposite" fertile? ("Opposite" meaning if it was a tet conversion and reverted back, it would be a dip ..... or a dip conversion reverting back to a tet.)

And what genetic traits would such conversions carry? If a tet conversion, would the genetics still contain the dip pedigree? Or would those dip genetic traits end when converted to tet (... or a reverse conversion of a tet to a dip)?

I came up with my own Daylily Pedigree template and this particular seedling pedigree chart shows the tet conversions in the genetic line:


Also, where does the pink petals come from? No "pink" back through the 4th generation. Could Celestial Eyes be pink? If so, would that petal color be considered a "recessive" gene?

beckygardener said:Maurice - Survival of the fittest? I guess it really comes down to research on cultivars and trial & error?

Yes, it would be more or less survival of the fittest, either because some of the plants do not survive or because some of them grow so poorly that the hybridizer discards them.

Maurice - Good point about the hybridizer discarding those that grow poorly.

I edited my post above yours and added a pedigree chart. I was really interested in my ZZZ66 seedling having pink petals. Recessive gene from where? Celestial Eyes color is described as "cream medium peach with medium slate violet eye and gold edge above green throat". So where is the pink coming from? Even further back? This is so fascinating!!!!