On a Facebook forum, I asked what hybridizers put in the baggy when they cold stratify. Everyone appeared to report that they "dry" store the seeds in the bags. I have been influenced by articles like the attached that say to "cold stratify" (store with some type of damp material; paper towel, perlite, vermiculite, etc.) Probably dampen with a little of the following mix: 1 tablespoon of hydrogen peroxide per pint of water. I was surprised by the dry storage. I just assumed some sort of wet "Cold Stratification" was being used. The only reason I even asked was I wondered if anyone used Sphagnum Moss which inhibits disease because of the high acid. But nowhere can I find that Sphagnum Moss is used. Any thoughts?
http://www.ctdaylily.com/files...
(However, I strongly feel that Cold Stratification applies to seeds from Dormant type plants.)

I just use ziplock bags with dry seeds for refrigerated storage. It works for me since I start pod harvest in June and don't start seeds until mid-October. At that point, I don't cold stratify here even dormant crosses from MI.

It's my understanding that stashing dry seeds dry in the fridge is for storage, and that they can be kept viable for up to several years this way. Well-hydrated dry seeds sometimes germinate in the fridge during storage even before moisture is applied. However, if one wants them to really think they have had a winter and germinate strongly, applying moisture with chilling- moist stratification- does the trick. They sure don't all seem to need it, but it triggers rapid and uniform germination like gangbusters! I think it's worth the effort to enjoy the efficient results.

It sounds like there are many ways to be successful at moist stratification, and it's a question of ease and preference. And your local climate and temperature matters. I have experimented with different ways.

For limited numbers of seed-starts, I like to use a cotton face pad soaked with hydrogen peroxide solution in a baggie in the fridge for 10 days or so. (This is what I plan on doing with all the seeds if I ever get my act together enough to start fresh-ish seeds in the greenhouse in fall. Artificial winter is needed before they land in greenhouse soil). Cotton pads are cheap, easy and clean, and I can see the seeds clearly and check their status. They don't need the perlite or a medium at this point. They just want to not be submerged in solution.

For larger efforts in early spring, I just plant the seeds in growing medium in cell trays or bigger pots, water, and put the pots in the cold garage or outside (for about the same time) where nature can chill them. (I like planting dry seeds that don't have fragile roots and shoots yet, and it's faster.) Then into a warm space they go and they all germinate within a week or 2.

To break seed dormancy the seeds need to have some internal moisture or they won't respond. If they don't have seed dormancy then they won't benefit from stratification. The same seed may possibly have seed dormancy at one point and not at another because seed dormancy can wear off in storage.

It's quite possible that people who dry refrigerate actually did not have seed dormancy, so the refrigeration was just storage. In studies even seeds from evergreen species benefited from moist stratification by germinating faster and more evenly. That latter is really the key, daylily seeds will germinate eventually regardless but some may take a long time, weeks or months if not damp chilled prior to starting You can't tell by looking at them or necessarily from their parentage.

It's quite possible that some people do not have daylily seeds that have seed dormancy. So you will get varying answers. In some cases the seeds are germinating despite what was done to them rather than because of.

Experiments were done in the 1950s as noted in the article on Rich Howard's website, as well as for that Daylily Journal article. In both cases a proportion of seeds germinated immediately without stratification so not all seeds in the batches had seed dormancy even though the parent (in the case of the DJ article) was a "dormant".and the seeds were selfed.

Storage and stratification are not the same thing. Refrigerator dry storage is to prolong the length of time the seeds remain viable, damp cold stratification is to break seed dormancy.

SunriseSide said:I just use ziplock bags with dry seeds for refrigerated storage. It works for me since I start pod harvest in June and don't start seeds until mid-October. At that point, I don't cold stratify here even dormant crosses from MI.

Thanks for the info. I am trying drying for one week, a limited test of soaking in 1% hydrogen peroxide (based on some studies) for an hour, rinse and going straight to room temperature germination in baggies with perlite. Trying to reduce the plant development time by a year. I am already collecting seeds and trying to germinate now June 13. The problem is I wonder if the "dry" cold storage you do improves the germination rate. Articles say no. It requires moisture in cold storage to help germination. But maybe cold dry storage does help.

Hembrain said:It's my understanding that stashing dry seeds dry in the fridge is for storage, and that they can be kept viable for up to several years this way. Well-hydrated dry seeds sometimes germinate in the fridge during storage even before moisture is applied. ....However, if one wants them to really think they have had a winter and germinate strongly, applying moisture with chilling- moist stratification- does the trick. They sure don't all seem to need it, but it triggers rapid and uniform germination like gangbusters! I think it's worth the effort to enjoy the efficient results.

Thanks! Your post is what I always believed except 3-4 weeks in cold, damp storage.

sooby said:To break seed dormancy the seeds need to have some internal moisture or they won't respond. If they don't have seed dormancy then they won't benefit from stratification. The same seed may possibly have seed dormancy at one point and not at another because seed dormancy can wear off in storage.

It's quite possible that people who dry refrigerate actually did not have seed dormancy, so the refrigeration was just storage. In studies even seeds from evergreen species benefited from moist stratification by germinating faster and more evenly. That latter is really the key, daylily seeds will germinate eventually regardless but some may take a long time, weeks or months if not damp chilled prior to starting You can't tell by looking at them or necessarily from their parentage.

It's quite possible that some people do not have daylily seeds that have seed dormancy. So you will get varying answers. In some cases the seeds are germinating despite what was done to them rather than because of.

Experiments were done in the 1950s as noted in the article on Rich Howard's website, as well as for that Daylily Journal article. In both cases a proportion of seeds germinated immediately without stratification so not all seeds in the batches had seed dormancy even though the parent (in the case of the DJ article) was a "dormant".and the seeds were selfed.

Storage and stratification are not the same thing. Refrigerator dry storage is to prolong the length of time the seeds remain viable, damp cold stratification is to break seed dormancy.

Perfect. Believe me, I read those studies over and over. Still not sure that totally applies to evergreens. Every study I've seen deals with dormants. All I crossed this year are solid evergreens. So doing some tests.

I did a test one year with no stratification and with cold moist stratification. It was several years ago, and I don't recall
much about the results, but I did start using cold moist stratification after that. So I must have seen enough different that it impressed me enough to change, and nearly all my seeds are evergreens.
Edited to add:
I do remember that my seeds were sprouting over a long spread out period of time, and with the cold moist stratification they cut that spread out time down quite a bit. I wanted my seed to all sprout pretty much at the same time.

Seedfork said:I did a test one year with no stratification and with cold moist stratification. It was several years ago, and I don't recall
much about the results, but I did start using cold moist stratification after that. So I must have seen enough different that it impressed me enough to change, and nearly all my seeds are evergreens.
Edited to add:
I do remember that my seeds were sprouting over a long spread out period of time, and with the cold moist stratification they cut that spread out time down quite a bit. I wanted my seed to all sprout pretty much at the same time.

That's it. The reason to do cold stratification.... uniform germination. I am doing something weird with one baggy now. In the frig at night; out in A/C in the day...like in real life. Cold at night; warm in the day.

bobjax said:

Perfect. Believe me, I read those studies over and over. Still not sure that totally applies to evergreens. Every study I've seen deals with dormants. All I crossed this year are solid evergreens. So doing some tests.

You mentioned studies with hydrogen peroxide, do you have a reference specifically for daylilies?

Regarding evergreens, it's possible that it has more to do with where the plants are grown than their registered foliage habit, @admmad has posted about that in the past. The other thing is where would you apportion those daylilies that are evergreen in warm climates but the same cultivar is "dormant" in colder climates (or vice versa as noted in some cases by Stout)?

As far as chilling un-dampened, it may have some minor beneficial effect but not as good as proper stratification. I think that is illustrated in the CT Daylily article. There is also a reference in that article to seeds from an evergreen species, Hemerocallis fulva var. littorea benefiting from stratification (Suzuki).

It's also possible that if people believe seeds from evergreen daylilies do not have seed dormancy and don't stratify, and don't wait for any slow ones to germinate, they they are breeding seed dormancy out of their daylilies. I have often heard of people tossing anything that didn't germinate within a couple of weeks or so on the assumption that they are either dead or "weak" whereas they may well have been seed dormant and just biding their time.

It's a fascinating topic and your experiments will be interesting - I assume you will make sure to leave some untreated seeds as comparison.

sooby said:

You mentioned studies with hydrogen peroxide, do you have a reference specifically for daylilies?
....

It's a fascinating topic and your experiments will be interesting - I assume you will make sure to leave some untreated seeds as a comparison.

No Daylily studies..Corn, peas, zinnias, chili peppers and more. That is why I will try it with a limited number of seeds. I have seen a full range of Hydrogen Peroxide formulas in various studies. 9.6 to 1 at 3%, all the way to 3 parts water to 1 part at 3%. All solutions did kill the diseases which is the reason most of these studies were done. They seem to indicate that germination can increase in some studies, some not. Too much can stunt root growth. https://www.researchgate.net/p...

Is that 1% total H2O2 or 1:99 household 3% hydrogen peroxide to water?

Hydrogen peroxide does appear to break daylily seed dormancy. When I tested it at various concentrations the stronger the solution the faster the germination (I left them soaking in it until protrusion of the radicle). What I should have done was follow through to see if there were any longer term negative effects on growth from the stronger solutions. My controls were plain water, and planting normally. Plain water soak resulted in worse germination than just planting without any pre-treatment for daylily seeds with seed dormancy. But of the two or three seeds that actually did germinate in plain water, their initial growth was better than those in the peroxide.

Quite a few people do germinate their daylily seeds in dilute hydrogen peroxide but once in a while I've heard of some seeds that don't respond and need to be stratified.

It is not unusual for daylily hybridizers to assume that cold stratification involves storing seeds dry in cool conditions. The assumption is not correct if the desire is to break seed dormancy since that involves cool moist conditions.

bobjax said:(However, I strongly feel that Cold Stratification applies to seeds from Dormant type plants.)

If seed dormancy in daylilies (cold moist stratification) applied only to seeds from dormant plants then it would be an inherited characteristic. However, characteristics are typically determined by the action of inheritance plus environment plus the interaction of inheritance with environment. To be determined by dormant type plants it would have to be purely inheritance.

One assumption about seed dormancy is that it prevents seeds that are mature from germinating late in the growing season. If they do so then they may not be able to grow large enough and store enough nutrients to survive until the next growing season.
As such it is basically a response of the seed to the environment that it experiences during the time that it develops on the pod plant. That can also include the environment that the pod parent experiences even before it starts to produce its flowers.
In a typical species seed dormancy or the lack of it can be an inherited characteristic since each species may have evolved to respond to a specific set of conditions. However, there are several important modifiers to the simple inheritance of seed dormancy.
One is that some species are present in many different locations with different climates and so seed dormancy may be advantageous in some parts of their home ranges and possibly disadvantageous in other parts. In such species seed dormancy may be strongly affected by the environment the seed experiences while developing.
The other applies to daylilies. The daylily gene pool or population is not derived from one species. It is derived from a mixture of a substantial number of species that have home ranges over wide areas. So it is quite possible that seed dormancy in daylilies is strongly affected by the environment that the seed experiences while developing.
As far as I know, no one has done the necessary test for daylilies. That would be to cross two cultivars in one environment where it would be advantageous for seeds to be dormant when they mature in the autumn. The same cross would need to be done in a different environment where it would not be advantageous for the seeds to be dormant when they mature in the autumn. Note, if the seeds mature at different times of the year/(growing season) that may be all that is required for the seeds to have more seed dormancy in one location than the other or for more of the seeds to be dormant in one location than the other.
A seed that matures late in a growing season has less time to grow and store resources than a seed that matures early in the same growing season. That in itself may be enough to change the probability that a seed will be dormant. A seed that matures late in a short growing season is likely to have a different probability of being dormant than a seed that matures early in a long growing season.

From one research publication,
"The environmental conditions experienced by plants during
seed development, known as the parental (or maternal) environment,
can influence seed dormancy in many species, and
thus seed dormancy is a plastic trait (Roach and Wulff,
1987; Donohue, 2009). When a seed is freshly mature, the
primary dormancy it displays developed while the seed
was maturing on the parent plant (Finch-Savage and
Leubner-Metzger, 2006; Donohue, 2009). During seed development,
maternal processes supply the seed with nutrients,
hormones, proteins and transcripts, which will influence the
seed's metabolism and gene expression (Donohue, 2009).
These processes can be regulated by environmental factors
such as photoperiod, temperature, water availability, vegetative
canopy development and nutrient supply (Fenner, 1991;
Gutterman, 2000; Donohue, 2009). The effect of a parental
environment factor may depend on the degree of stress that a
particular plant perceives. In particular, the effects of parental
photoperiod and temperature on dormancy show trends that are
consistent among a range of species, with seeds that develop in
a warmer environment or with shorter days often being less
dormant (Fenner, 1991; Gutterman, 2000; Donohue, 2009).
The effect of parental water supply is not as clear
(Gutterman, 2000); the majority of studies show that seeds
that develop with a lower water supply are less dormant (e.g.
Arnold et al., 1992; Meyer and Allen, 1999; Luzuriaga
et al., 2006). However, other studies have shown no effect
(Swain et al., 2006; Hoyle et al., 2008a, b) or even an increase
in dormancy (Sharif-Zadeh and Murdoch, 2000)."

From "Parental environment changes the dormancy state and karrikinolide response of Brassica tournefortii seeds" in Annals of Botany, Volume 109, Issue 7, June 2012, Pages 1369–1378

sooby said:Is that 1% total H2O2 or 1:99 household 3% hydrogen peroxide to water?

Hydrogen peroxide does appear to break daylily seed dormancy. When I tested it at various concentrations the stronger the solution the faster the germination (I left them soaking in it until protrusion of the radicle). What I should have done was follow through to see if there were any longer term negative effects on growth from the stronger solutions. My controls were plain water, and planting normally. Plain water soak resulted in worse germination than just planting without any pre-treatment for daylily seeds with seed dormancy. But of the two or three seeds that actually did germinate in plain water, their initial growth was better than those in the peroxide.

Quite a few people do germinate their daylily seeds in dilute hydrogen peroxide but once in a while I've heard of some seeds that don't respond and need to be stratified.

Very interesting to read about your tests. Do you remember what strength you used? The dilute formula, like 1 tablespoon to a pint of water seems to me to be for disease control, although I've read 2 tablespoons for that.
I have seen studies from 19.6 to 1 at 3% up to 3 to 1. It seems the purpose is to kill pathogens but they also study germination, and root growth, etc. Not convinced about germination per some of these studies. https://www.researchgate.net/p...

admmad said:
As far as I know, no one has done the necessary test for daylilies. That would be to cross two cultivars in one environment where it would be advantageous for seeds to be dormant when they mature in the autumn. The same cross would need to be done in a different environment where it would not be advantageous for the seeds to be dormant when they mature in the autumn. Note, if the seeds mature at different times of the year/(growing season) that may be all that is required for the seeds to have more seed dormancy in one location than the other or for more of the seeds to be dormant in one location than the other.

I'd love to see a study like that. You're the expert but in my amateur opinion, I feel that a daylily has a dominant gene that says it will be, for example, an evergreen. Just like the mix of colors that are in the gene pool for one particular daylily, but it blooms as yellow. The creation of the seeds in different environments could make a particular gene become dominant. But I will never know if that is true.
Incidentally Maurice, I have two pods of the self-pollinated Korean Fulva still looking very good. Also I am harvesting seeds off the dips. Half the pods dropped but I am getting nice seeds. The Tet has not dropped one pod and are big pods some getting ready to open. I am speaking about my self-pollination test.

bobjax said:
Very interesting to read about your tests. Do you remember what strength you used? The dilute formula, like 1 tablespoon to a pint of water seems to me to be for disease control, although I've read 2 tablespoons for that.
To softened the skin to speed germination, I calculated it at 1 cup (for example) of 3% and two cups of water to get to a 1% solution. But I'm a little confused because somewhere I saw that it is 1 cup to three cups to get to 1%. The whole concept is about weakening the outer skin so water can get in. Griesbach actually found very good results by cutting the skin away. But I'm definitely not doing that.

Commercial hydrogen peroxide is at a higher strength than the drug store version. I used the household hydrogen peroxide which is 3%, further dilutions shown below. The seed coat of a daylily seed is not impermeable to water, it doesn't need softening. The inhibiting effect is a membrane in one area underneath the seed coat according to Griesbach, which limits oxygen exchange.

So it's not like the kind of seed dormancy where a hard seed coat is the cause of seed dormancy. Hydrogen peroxide has been shown to break seed dormancy in some other seeds by a biochemical pathway/interaction, I don't remember exactly what was proposed. It has also been suggested that the H2O2 increases the amount of oxygen and assists in that way with other seeds.

Results after 18 days:

100% H2O2 soak = 13 germ 12 not germ
1:3 19 germ 6 not germ
1:5 13 germ 12 not germ
1:7 10 germ 15 not germ
1:9 10 germ 15 not germ
1:11 10 germ 15 not germ
1:13 9 germ 16 not germ
1:15 11 germ 14 not germ*
Plain water soak 2 germ 23 not germ*
Damp vermiculite 1 germ 24 not germ*
Control

Solutions for all changed for first time on 23rd August when counted.

Results after 4 weeks

100% H2O2 soak = 22 germ 3 not germ
1:3 25 germ 0 not germ
1:5 25 germ 0 not germ
1:7 20 germ 5 not germ
1:9 22 germ 3 not germ
1:11 23 germ 2 not germ
1:13 20 germ 5 not germ
1:15 18 germ 7 not germ
Plain water soak 4 germ 21 not germ
Damp vermiculite 7 germ 18 not germ
Control

From my notes: Weaker H2O2, water and vermiculite seedlings fewer but more advanced. H2O2 seems to break seed dormancy, speeding germination, but inhibit growth at least in the solution. Seedlings were not grown on to see if this was a permanent effect.

Going back to evergreen versus deciduous ("dormant") daylily's seeds, if it was the case that seed dormancy was related to foliage habit of either the parents or the future foliage habit of the seedling, then why do a percentage of seeds from the same parent x same parent germinate immediately and some not for some time unless stratified?

In the tests I did the seeds were from a selfed deciduous species-type daylily. Are you implying that the 25% that germinated immediately without stratification would have been evergreen?

@Sooby

These results suggested to me that the differences in concentration did not have a significant effect on the germination. So I did a chi-square test. The result indicated that the differences could be explained as random for the 100% to the 1:15 ratio at 18 days. However, there seemed to be some significant differences at four weeks (although the chi-square test is supposedly less reliable with smaller values).
I also checked for trends of germination with concentration by calculating regressions for both time periods. There was no evidence for trends of germination increasing or decreasing with a change in concentration.

@bobjax
For foliage or growth characteristics to be related to seed dormancy characteristics they would either have to be the same gene or two very closely linked genes - therefore effectively acting as one.
Stout determined that "evergreen" was dominant to "dormant". We can label "dormant" daylilies as dd and "evergreen" daylilies can be either Dd or DD.

A "dormant" (dd) daylily can be crossed with DD, Dd or dd.
dd x DD produces only Dd or "evergreen".
dd x Dd produces 50% of each
dd x dd produces only dd

An "evergreen" (DD) daylily can be crossed with DD, Dd or dd.
This only produces "evergreen" either Dd or DD.

And lastly an "evergreen" (Dd) can be crossed with DD, Dd or dd.
Dd x DD produces only "evergreen"
Dd x Dd produces 25% DD 50% Dd and 25% dd
Dd x dd produces 50% Dd 50% dd

A proportion of "evergreen" x "evergreen" crosses would produce 25% seeds that were dormant.
"dormant" x "dormant" can only produce seeds that are dormant.

I suspect that some "dormant" x "dormant" crosses produce at least some seeds that are not dormant. That would not be possible if foliage/growth habit and seed dormancy are genetically the same..

sooby said:

Commercial hydrogen peroxide is at a higher strength than the drug store version. I used the household hydrogen peroxide which is 3%, further dilutions shown below.
......
In the tests I did the seeds were from a selfed deciduous species-type daylily. Are you implying that the 25% that germinated immediately without stratification would have been evergreen?

Amazing info. Thanks!
You know about hypotheses. Sometimes they are right; sometimes they are wrong or partially right/wrong. So yes, at this moment I am hypothesizing "that the 25% that germinated immediately without stratification would (could) have been evergreen." That is what I am studying. If I could find one study that actually shows that it is mostly wrong, then I will believe it. Why is that important to me? Because I have very limited space I don't want plants that have rust or that are dormants. I want a solid green presentation throughout the winter because my main garden faces the street. Last winter I had all evergreens and it looked great in the winter. The blooms looked great in the spring. Now it doesn't look so good since I culled so many plants to make space for new seedlings. So, I am not a scientific, big-time hybridizer, just a small-time gardener, who loves my beautiful beds. And because of my 27 years running research departments, I like to do research, like some people like playing golf.

admmad said:@bobjax
For foliage or growth characteristics to be related to seed dormancy characteristics they would either have to be the same gene or two very closely linked genes - therefore effectively acting as one.
Stout determined that "evergreen" was dominant to "dormant". We can label "dormant" daylilies as dd and "evergreen" daylilies can be either Dd or DD.

A "dormant" (dd) daylily can be crossed with DD, Dd or dd.
dd x DD produces only Dd or "evergreen".
dd x Dd produces 50% of each
dd x dd produces only dd

An "evergreen" (DD) daylily can be crossed with DD, Dd or dd.
This only produces "evergreen" either Dd or DD.

And lastly an "evergreen" (Dd) can be crossed with DD, Dd or dd.
Dd x DD produces only "evergreen"
Dd x Dd produces 25% DD 50% Dd and 25% dd
Dd x dd produces 50% Dd 50% dd

A proportion of "evergreen" x "evergreen" crosses would produce 25% seeds that were dormant.
"dormant" x "dormant" can only produce seeds that are dormant.

I suspect that some "dormant" x "dormant" crosses produce at least some seeds that are not dormant. That would not be possible if foliage/growth habit and seed dormancy are genetically the same..

Excellent information! Thanks!