Sabrina,
Your temperatures are better than fine - a night as warm as 65 degrees here is a rarity, and daylily seedlings thrive. Granted, they won't grow as fast as yours will, because when the nights cool off to 55 at dusk, a good part of the next morning is spent getting the plants up to growing temperature. When the weather warms up in late summer and the nights are 60-62 until 11:00 pm, I see improved growth in all plants.

Daylilies evolved in temperate zones, and, unlike tropicals, a fluctuation between day and night probably does them good, as does a change in season. I think if you can figure out some simple method of fortification that will prevent animal damage, there's no reason to bring them back inside, ever. My fall-planted seedlings, even in a mild year, will see plenty of light frost in the form of 30-32 degree nights from late December through February, and there are few, if any losses. Properly handled and grown, given lots of light, your winters are no challenge to a daylily at practically any stage of growth. I've seen volunteer daylily seedlings sprouting in the garden in the middle of winter, and they just grow very slowly until spring comes. The most rudimentary of cold frames, set near the foundation on the south or southeast side of a building would be fine. Your biggest threat might be from excess moisture if you get a lot of rain in the winter - particularly if the soil mix is water-retentive.

Sue,
The last time I shopped Miracle-Gro, their standard mix was 15-30-15, but I was able to find their tomato and vegetable formulation, and the nutrient ratio was similar to the numbers you gave.
My seedlings are definitely kaput - they were in full sun and received the full brunt of our Indian Summer. Also, they were in a 50-50 coir/perlite mixture that I was trying out. They were up off the ground, so it was as if they were in an oven, and the foliage turned that ugly gray-green and collapsed in rot. I checked - there's nothing under the soil but cooked roots. The weather and conditions just caught me off-balance. The whole flat didn't die off, maybe 30% of the seedlings. The fact that the survivors are probably tough-as-nails is my consolation.

Ken
East S.F. Bay Area
USDA Zone 9 - mediterranean

Ken - Thanks a lot for your reply. I have some problem in finding the right spot to put DLs outdoors, I have a terrace that faces east but that's my cats' realm, and cats won't leave any plants alone. The little garden is at the entrance of the house, and it faces west. I can put DLs near the walls and 80% of times when it rains they will be covered from a little roof (I am at the ground floor, and at the second floor there's another apartment so roof is high). But when rains are strong everything gets wet, sometimes water get into the house from windows. Sun hits the garden for very few hours and not until middle noon.
As for freeze, the last two years winters were mild but until two years ago we were used to get freeze (14 - 23 F) from december to february. Weather has got crazy here, I don't know what to expect for next winter.
I'm pondering on what to do, apart from the crazy cat I know sometimes other cats go around at night because I hear catfights. Apart from that no other critters are around. maybe I can put them out now, and if winter will be hard I'll buy a little movable cold frame.
Could it be an idea?

To put winter temperature into perspective, 'Stella do Oro' does fine here where the winters go down to -30 degrees C (-22 degrees F) and sometimes below, often with very little insulating snow cover.

There are all sorts of plastic baskets that could be used to protect the seedlings from animals outdoors, and also make it easy to carry them indoors and out if the weather forecast is bad - here's a selection from Google for some ideas:

https://www.google.ca/search?q...

There are also laundry baskets and various other possibilities. If you think the cat/s will try and get in the basket with the plants if the open side is up, then while the plants are small invert the basket over them instead, or else put a second basket, sheet of plastic, bird netting, the hardware cloth that CaliFlowers suggested or something similar over the top.

A cold frame is certainly an option also but would be more expensive if you buy it instead of making it or converting something else and you'd have to be careful that the interior doesn't get too hot in the sun.

CaliFlowers, I think the change in Miracle Gro was fairly recent (past couple of years or so) but 24-8-16 now seems to be the standard analysis for All Purpose:
https://www.amazon.com/dp/B000P6QYJK/
Like you I used to prefer the tomato one before.

Edited to add picture of plants "parked" in a milk crate to keep them safe from munching wildlife:

many thanks Sue! The pots are outisde. they're getting sun now (it's 3 PM here) .
The little seedling has started the third leaf, the other seeds are still seeds . I checked for humidity, vermiculite is still damp and I'll try to check constantly, and for now no signs of cats.

Open boxes are commonly called "traps for cats", they just can't resist when they see a box of whatever material they have to get inside!
Starting from tomorrow wheather should change, temperature should drop and we're expecting rains.

I am not really concerned about adult plants, they all survived to their first winter, I'm afraid for the little seedlings, giving that I will put them in pots and not in the ground (I haven't decided yet, I have to clean a big spot before and don't know when I'll be able to do it).

A home made cold frame should be fine if the winter will be very cold, otherwise they will be in open air. Could it work?

cybersix said:

Open boxes are commonly called "traps for cats", they just can't resist when they see a box of whatever material they have to get inside!

Yes, that's what I was thinking. You don't think the suggestions I made above for dealing with that would work?

cybersix said:
I am not really concerned about adult plants, they all survived to their first winter, I'm afraid for the little seedlings, giving that I will put them in pots and not in the ground (I haven't decided yet, I have to clean a big spot before and don't know when I'll be able to do it).

A home made cold frame should be fine if the winter will be very cold, otherwise they will be in open air. Could it work?

Seedlings indeed can be less hardy than they would be once they've "grown up" but your climate doesn't get very cold. A danger is if the temperature suddenly dropped a great deal before they have had time to acclimate to cold, and you are right that being in a pot makes them more vulnerable to temperature fluctuations. Yes, a cold frame would work, you just have to make sure not to keep it tightly closed when it is sunny, and you may need to put some shade cloth or a shade wash on the glass/plastic.

Again, with the door to the cold frame open or ajar, you may have problems with cats getting in - after all they do like to sit where it's warmer!

The average lowest winter minimum for zone 9 is -6.6 C (20-30F). I don't think you need to worry about the seedlings being outdoors except on nights when it might actually get to that lowest temperature or progresses nearer to zone 8. On nights when it is expected to go below freezing you could bring them into the house or cover them.

Do the leaves of your adult plants die back in the winter there?

Sue, putting the box downside will sure work, sorry I wasn't clear at all!
I was thinking about a cold frame only if it should freeze. Again, next winter to me it's unpredictable. We were used to get freezing nights and mornings almost all winter long, but in two years things changed a lot. Mild winters, lots of rain, and not so hot summer with lots of rain too. In the past two years I remember it frozen just one night.
This past summer was very hot and dry instead, so who knows what kind of winter will come?
So I'm not sure I chose my climatic zone well. Weather is really crazy here and seasons are no longer the same.
The past mild winter only Stella de Oro lost all foliage as I was expecting, the others kept some leaf here and there. I only have registered cultivars, Stella is the only dormant, the others equally divide in SEV or EV.
They are quite new to my garden, Stella was planted in august 2013 and the others in march 2014. I don't know them very well yet.
My crosses are both a SEV x EV.

The reason I asked about foliage dying back was to get an idea of how the daylilies handle the cold that they do get there, because in colder climates they would all die back, whether registered as dormant, semi-ev or ev. If yours don't die back much then the seedlings may be OK outside, especially if you could pull the pots back against a house wall on colder nights. If you decide to plant them in the ground they are more protected but less portable. If it gets too cold they may die back and go dormant but not necessarily die.

I did garden in zone 8/9 in southern England for the first part of my life and there I don't think I would be worried about the seedlings overwintering safely outdoors but I didn't grow daylilies back then (well, I did have one I must admit).

It would certainly be useful to have a cold frame if you can make one relatively inexpensively but for just a few plants it might be easier to just bring them indoors or otherwise protect them if you do get much below freezing (I don't think a few degrees below freezing would hurt them).

Sorry...
Another question!
Since I put the pots outside daylilies seem to have stopped. One has three leaves and no signs of other; one seed has sprouted and I can see a couple of millimeters peeking out from vermiculite but it's three days that it stays the same. The other seed doesn't sprout.
Temps have lowered, about 50F at night and 59F at day. Are these temps too low for seeds to sprout? I am ready to bring them back inside and maybe getting a cheap LED light for them, since there is no bright spot in the house. Inside the temp is about 68F.

The amount a plant grows depends on temperature (as well as other factors) so the seeds will take longer to sprout and grow more slowly when the temperature is lower.

Thank you Maurice.
So they won't have any problem apart from a slower growth?

You are welcome.
That is correct - they will not have any problems apart from slower growth.

Since you're working with a small number of plants, you can afford to give them micro-attention, so at this point you should probably have the unsprouted seed in a separate pot, since you might want to handle it differently than the plants.

As Maurice said, it's not too cold for seeds to sprout. Most of my seeds sprout in the refrigerator (35F) after three months. Theoretically a seed will tend to sprout faster at warmer temperatures, but as a practical matter, right now there's really not that much temperature difference between inside and outside. There are other factors which affect sprouting. If you leave it outside it will benefit from the day/night temperature swings plus the warming effect of the sun shining directly on the soil, which should raise the temperature of the seed well above ambient for a few hours each day. Both of these things are known to promote quicker germination. If the weather gets chilly, but remains sunny, you could put some sort of cloche over the pot with the seed in it -- just make sure to not fully enclose it, otherwise you'll overheat the seed if you get an unexpectedly warm day.

Also, be prepared for the last seed to never sprout at all. Some seeds are defective, have poor disease resistance, or some other genetic factor which makes them less robust than a "normal" seed. I'm a firm believer in not using extraordinary measures such as fungicides and soil sterilization to ensure that every seed produces a plant. Sensitive, rot-prone plants simply weaken the gene pool. I think everyone at some point buys a daylily which just doesn't have "it" with regard to vigor, hardiness, or simply a will to live. This is a random thing, for sure, but fungicides, pampering and cushy, sterile growing conditions don't help.

Regarding your seedlings, as long as they're getting bright sunlight, I think the plants will still do better outside for a while - even with the recent dip in temperatures. With the moderate weather you're getting now, they should be able to take direct sun. Even if you don't see much leaf growth, they're still gathering energy and probably developing better roots. You can also feed them lightly, as long as they're getting strong light.

It's hard to beat the sun. There are artificial lights available which would be a pretty good substitute for natural sunshine, but they're expensive. Lighting does help with another aspect of growth though, and that is to modify the photoperiod. If you really want to give the seedlings a good head start, you could leave them outside during the day, bring them inside before sunset and stage them under a bright light until 10:00 or so, then set them back outside in the morning. This will provide a long photoperiod, keeping them in full 'growth mode', while still letting them get the benefit of full sun in the daytime. They'll also have the benefit of starting their day with an already-warmed pot of soil. Don't be surprised if they require larger pots before shutting them down for winter.

If you do the photoperiod trick, sometime around mid-November you should just leave them outside in a sunny, protected area so they can slow down naturally for the winter. This "extended summer" combined with a cold period will probably give you the best chance of seeing a bloom by next fall.

You could also go all-out and continue to grow them inside/outside, using the light throughout the winter. They'd be bigger next spring, but some people believe that a winter rest is a necessary trigger for good spring growth -- particularly for a deciduous variety. You probably won't be able to tell this winter if your seedlings are evergreen or deciduous, since small, freshly-sprouted seedlings will have a tendency to grow for six or seven months before going dormant for the first time. You can't always predict growth habit from the parentage either -- daylilies have been crossbred so much that a cross between two evergreen varieties often produces a few deciduous (or dormant) plants, and vice-versa.

As far as I can tell (and from some information from researchers) photoperiod by itself does not appear to have much effect in daylilies. As a simple test I have brought daylilies inside during late December and early January and placed them where the light they received was from outside. They broke dormancy and grew throughout the rest of the winter even though they were experiencing very short days and long nights. The amount of light the plants receive is different between short days and long days and more light does allow plants to grow more (within reason) but the same effect can be produced by higher intensity light (within reason).

Stout indicated that for daylily foliage types (as he defined them) evergreen was dominant to dormant. That would mean that sometimes two evergreens crossed together could produce some dormant seedlings (depending on the genetic backgrounds of the particular evergreen plants) but that two dormants crossed together should not produce any evergreen seedlings. The catch is that foliage types change depending on the winter weather (nearly all cultivars registered as evergreens appear to be simple 'dormants' in my zone 4 climate) . It is also very unlikely that foliage types or growth characteristics (the alternative phenotype to evergreen is deciduous; the alternative phenotype to dormant is ever-growing or non-dormant) are inherited as simple single Mendelian genes.

Maurice, could that emergence from dormancy be a matter of timing?

In your climate, by late December it seems as if daylilies grown outside would have already experienced quite a bit of both photoperiod (assuming it exists) and/or cold-induced dormancy, and when introduced to warm conditions, they would begin to grow, and once doing so, the hormone cycle set into play might overpower the photoperiod effect.

What I've noticed here regarding photoperiod-induced dormancy is on the other end of the growing season. Despite fair temperatures, (not even light frosts at that point) many dormant daylilies are down to hard crowns by Thanksgiving. This is what led me to think that photoperiod was involved. What do you think is going on there? Is it a matter of the plants having produced a "season's worth" of leaves and blooming stems, triggering a rest period? Might it have something to do with the plants being sensitive to increasing day lengths in January and decreasing day lengths in autumn? Put another way, could it be that the plants are able to sense that each day is longer than the last, and that alone is enough to maintain a growth cycle?

I'd appreciate hearing your thoughts about all this.

Ken

Thank you both Maurice and Ken.
Here the problem is sun light, we have very few in autumn and winter. I guess because we live just under some hills/low mountains, and when weather is not 100% clear here we have always clouds (infact when I move from my house down to the city I always find different light and temps). Autumn and winters there's poor sunlight.
The house is dark, too, I can't use windows interior sills because of the cats, so there's no good spot close to the windows.

In these days I see a good growth on DLs that are in the ground, most of them are growing new fans, I'm only talking about my seeds and my freshly sprouted seedlings.
I wanted them to grow as big as I could before next spring but maybe it's simply not possible due to environmental conditions.
I guess I will bring them back inside until they are grown a bit, then put them in bigger pots and put them again outside, since bigger pots won't fit anywhere inside (should I prefer deep pots or large pots for roots?)
Do I have to prefer warmth or light?
As a side note, do any of you know if DLs are toxic for cats? Many plants are, but I can't find any information here since they are rarely grown.
Many thanks!

CaliFlowers said:Maurice, could that emergence from dormancy be a matter of timing?

In your climate, by late December it seems as if daylilies grown outside would have already experienced quite a bit of both photoperiod (assuming it exists) and/or cold-induced dormancy, and when introduced to warm conditions, they would begin to grow, and once doing so, the hormone cycle set into play might overpower the photoperiod effect.

I have also looked at growth and dormancy earlier in the year. I have brought dormant daylilies inside in both November and October. In all cases and all cultivars I have looked at so far the plants start right back into growth and continue even though they are experiencing short days (biologically actually long nights). They do not grow very quickly but they do break bud and grow.

What I've noticed here regarding photoperiod-induced dormancy is on the other end of the growing season. Despite fair temperatures, (not even light frosts at that point) many dormant daylilies are down to hard crowns by Thanksgiving. This is what led me to think that photoperiod was involved. What do you think is going on there? Is it a matter of the plants having produced a "season's worth" of leaves and blooming stems, triggering a rest period? Might it have something to do with the plants being sensitive to increasing day lengths in January and decreasing day lengths in autumn? Put another way, could it be that the plants are able to sense that each day is longer than the last, and that alone is enough to maintain a growth cycle?

It is possible that daylilies respond to the direction of changes in day length (biologically actual responses are to the night length). I don't think that is what is happening.
Plants adapt their growth to their environmental conditions. Unfortunately daylilies appear to be very adaptable in that manner. I have done a number of tests with 'Ophir' looking at its growth patterns. I have a bed with a row of 'Ophir'. The bed has not received any fertilizer in 20 years and it has never been watered (it receives only rainfall). It is weeded only once every few years and the plants in the bed had never been divided (almost natural wild growing conditions). Most of the 'Ophir' plants in that row produce a scape and stop producing new leaves at the same time. The scape appears in June and typically no new leaves are grown after that. Leaves that had been produced before then continue to grow and become longer. For some of the plants and in some years new leaves are produced after the scape appears. In those cases they stop being produced in mid-July. It tends to be the juvenile fans (that did not produce a scape) that continue to produce new leaves. Even though no new leaves are produced the crop of leaves survives until late October or early November. By then it has yellowed, fallen to the ground and is in the process of dying and drying. The bud that will be next year's fan is present underground in July. It slowly becomes larger but does not appear above ground before snow falls. I have brought fans of 'Ophir' from that bed inside as early as Oct 15; they sprouted from their buds and grew. I dug fans from that row in July one year and tested several groups. One group I simply left as is with scapes and leaves. A second group I removed the scape. A third group I removed the leaves and a fourth group I removed the leaves and scapes. All groups were put into water. The groups that had no leaves sprouted their buds first. Unfortunately as time passed the original leaves on the two groups (1 & 2) died (water was not enough to keep the fans healthy) and they also sprouted new leaves. However the conclusion appears that the presence of green leaves kept the bud from sprouting more than the presence of a scape and flowers.
The 'Ophir' in that bed have a growth pattern that appears to be dormant. 'Ophir' is registered as semi-evergreen and as a rebloomer. In that bed, with its dormant growth 'Ophir' would not be able to rebloom. However, Florida and California hybridizers indicate that nearly all cultivars rebloom in their growing conditions. So I changed the growing conditions for 'Ophir' for my next test. Some fans were planted in a raised bed of fresh soil that had been turned over and the sod rotted down and incorporated. Other fans were planted into a fresh bed and fertilized with plenty of nitrogen, watered and weeded. It took a year of growth before any of the fans produced scapes. In that second year 'Ophir' had a different growth pattern in both new locations. It produced new leaves all growing season and rebloomed.
I also tested 'Wynnson', a registered dormant by placing fans in water and observing whether new leaves were produced (bud break). It acted like 'Ophir'. However, Wynnson does (usually) behave differently from 'Ophir' in the autumn. Some of its fans break bud in September even when growing under quasi-natural conditions. However, it also continues to produce new leaves when grown with fertilizer, watered and weeded - like 'Ophir'.

'May May' is registered as a semi-evergreen rebloomer. Here it has lost almost all of its leaves; it did rebloom and it has broken bud with new fans and fresh leaf growth appearing. It is the only cultivar in many hundreds that I have noticed senesced (its leaves yellowed and died) so early this year. There is one other that tends to senesce early and that is a Siloam.

What I think is happening involves both the growth of the fan and leaves, the aging of the leaves and their effect on bud break and the production of a scape.
The growth behaviour of daylily fans is probably different depending on whether the fan is juvenile or mature. Mature fans are presumably large enough to bloom in their growing conditions while juvenile fans are not. If size is what determines the ability to flower then it may not be size of the fan; it may be size of the leaves, total photosynthetic area of the leaves, size of the growing point or shoot apical meristem (SAM) and whatever it is will be dependent on growing conditions. I have looked more at the growth patterns of mature fans.
A mature fan has one active growing point (SAM). It produces leaves and then switches over to producing the scape and flowers. When it does so it is finished and new leaves can only be produced normally by an axillary bud breaking/sprouting. Leaves can only live so long. They have natural lifespans and when they get to be a certain age they will die. They can also die due to environmental conditions. The leaves of many perennial plants produce compounds that prevent axillary buds from sprouting. Whether the leaves do prevent axillary buds from sprouting also depends on the environmental conditions. It is also possible that photoperiod changes cause leaves to die.
In some daylily cultivars and under some growing conditions when the SAM produces the scape an axillary bud will break and new leaves will be produced. The end result is that the fan may produce new leaves continuously throughout the growing season or there may be a short break in new leaf production that is more or less not noticeable.
In other daylily cultivars and under some growing conditions when the SAM produces the scape no axillary bud breaks and new leaf production stops for the growing season. In some of these cultivars when the leaves start to die (usually in the autumn) and under some growing conditions the axillary buds break and new leaves are produced that year/growing season. In some other of these cultivars when the leaves start to die and under some growing conditions the axillary buds do not break and no new leaves are produced visibly above ground.

I will be bringing some daylily plants inside this winter to test whether short days/long nights cause leaves to age and die.

Pretty impressive, Maurice.

Thanks for the enlightening & informative post.

That's a really complicated post for me Maurice, but many thanks for sharing your knowledge.

In the meanwhile here temp keeps on going lower, the first seedling is stuck with the three leaves it already had a week ago.
I planted it in a pot.

The others seeds sprouted and are still in vermiculite.
I'm still pondering on what to do, indoors or outdoors.
As I was expecting every day is cloudy so no sun light hits the pots.