I have mentioned scape density and it has been mentioned by others in a few threads. It was asked if there were a thread about it here on the forum, I did not find one. If there is one please direct us to it. Also many of us are not that familiar with the term, and I would love to get feedback in the form of actual plant experience but also any articles are research about it. I know that it relates to plants that put out a lot of scapes, compared to plants of similar size and age. How to you find these plants, what are the pros and cons? Do the plants stress themselves by producing more scapes and become weak after just a few years? Are there signs to look for in new plants that would be a tip off that the plant might process this trait? Any feedback appreciated!

@Seedfork Classifying daylily clumps by scape density implies that the flowering time of different fans/ramets in the clump will be more or less synchronized. Different fans/ramets in a clump are most likely different sizes and ages. I assume that something, synchronizes the flowering of different sized fans/ramets (that are above the minimum size for flowering or that are reproductively mature). I assume that is caused by periods of time when active growth stops either because of low temperatures or high temperatures. Scape density will presumably be lower at any given time if the flowering of different fans/ramets in a clump is not synchronized.

I have been growing nine pots of 'Stella de Oro' inside for 19 months. They have not experienced winter cold since the winter of 2018/2019. All the fans were of flowering size when they were brought inside. The scape production cycles were more or less synchronized between pots until at least 6 months of growth inside. They are not synchronized now. The average time between scapes in each pot is between two to three months. Nearly all of the pots have three to four fans. The pots were started as single fans in September of 2019 and were reduced to the largest single fan again in June of 2020.

Are there locations were daylilies are grown and each episode of flowering of each cultivar is spread out over longer periods (not as well synchronized) as in other locations (better synchronized)?

@admmad
I had not associated scape density with synchronized flowering. I guess I am not understanding exactly what "Scape density is"? I thought it just meant that the plant sends out an above average...more than normal... a lot of scapes compared to other plants. I don't know any specific number that determines great scape density, or have a list of plants that would meet the definition of scape density? I was just assuming that the scapes would be appearing regularly through out the season and would be blooming as the scapes matured, and that there would be a lot of them, but was unaware that synchronized blooming was even a thing. Makes me visualize ladies swimming with daylily bloom on their swim caps.

@Seedfork
From Hortaholic's post
" how many scapes are there "per square foot of clump"? Do you see a bouquet of flowers on top surrounded by a ruff of foliage? (Dense, and probably mostly straight scapes) Or do you see a lot of foliage dotted with a flower here and there? "

I assume (hopefully correctly) that a high scape density implies that many fans/ramets are flowering more or less at about the same time and that a reasonable proportion of all the fans/ramets in the clump are flowering at that time. That implies that a reasonable proportion of fans/ramets are mature size and that they started developing their scapes at more or less the same time (more or less synchronized).

For example a high density of scapes might mean a clump of ten fans/ramets with six (or more) fans/ramets flowering at the same time. If each fan/ramet only flowered once in a growing season then that would be a total of six (or whatever number) scapes. However, a clump of ten fans/ramets might flower at one time with four scapes and then might flower later in the same growing season with two fans. The blooming of the first clump was synchronized and had a higher scape density than the blooming of the second clump which was not as well synchronized.

Then there is the possibility that one clump might flower with a high density of scapes but only flower once a growing season while another clump might flower with a lower density of scapes but rebloom and flower twice a growing season. The total duration of flowering of the second clump might be noticeably longer than that of the first clump but the density of scapes at any one time would be much lower.

Scape density could be something measured during each separate period of flowering or it could be something measured over the whole growing season.

Is scape density as relevant as flower density? One clump might have ten scapes and 15 fans/ramets but only open an average of five flower buds per day. Another clump might have far fewer scapes but open more buds per day, for example say six scapes and 15 fans/ramets but open six flowers per day. Scape density and flowering period may interact and one may be more important for some gardeners but not for other gardeners.

So I suppose a daylily could have high scape density for just a very short period. I had not thought of that, I was thinking more along the lines of a lot of scapes at one time, but also over a long period of time. I can see now that if a plant had a flush of new spring scapes and they all bloomed out over a week or two, that could still be considered a high scape density plant. It could certainly have a lot of scapes per square foot of clump, just not for very long.
I suppose there are not any set numbers, percentages, or period lengths before the term can be applied. So like other stats, it's meaning is relevant only when seen in the garden.
So it is unlikely that a plant with well branched scapes would likely have high scape density? Would the scapes on high scape dense plants normally have a high bud count?

So I went looking for info on scape density: I found this short article about zone 4 hybridizers by Charlie Zettek who was mentioned earlier in another thread.
http://www.ahsregion4.org/docu...
I can now see why scape density would be so important to him, working with such short plants great branching would not be a much valued attribute. The flowers would be down in the foliage. So that would naturally make scape density more important for a good display of blooms.

This is from the abstract of research on a species of grass,
"Vegetative ramets translocated their own resources to the connected reproductive ramets, and a large proportion of translocated resources were allocated to the leaf and stem to sustain life activities; increase in the number of connecting vegetative ramets increased floret number, seed number, seed-setting rate, inflorescence biomass, seed biomass, and reproductive allocation of reproductive ramets, and these parameters significantly and positively correlated with the biomass of connecting vegetative ramets."

If a similar situation occurs in daylilies then the more non-flowering fans/ramets in a clump the greater the number of flowers on the scape, the number of developing pods the scapes can support, the number of seeds in those pods, etc. (as long as the daylily fans/ramets in the clump are connected).

I guess the question is does a similar situation occur in daylilies?

@Seedfork
My guess is that whether a similar situation occurs in daylilies may depend on the "age"/size of the "daughter" non-flowering fans/ramets. A newly developing offspring fan/ramet requires resources from the parent fan/ramet until it has grown sufficiently mature leaves and developed its own roots. After that initial time, when the new fan/ramet is established, the direction of resource flow (in some species) depends on the circumstances of the parent ramet/fan versus the circumstances of the offspring ramets/fans.

Typically determining whether a similar situation occurs in daylilies would be answered using isotopes in a professional research lab setting - that is unlikely to happen any time soon for daylilies.

However, perhaps a simpler test is possible for daylilies.

That might involve comparing the growth and flowering of single fan divisions versus double fan divisions. In one version of the test the double fan divisions would need to have the approximate same size crown and roots as the single fan divisions and of the two fans, one would need to be the same size as the fan of the single fan division and the other could be an intermediate size fan (that was large enough to no longer likely require support from its "parent" fan but not so large that it would be able to flower). Naturally, there would need to be some number of such single fan and double fan plants (replicates). In this version of the test the question would be whether the leaves of the non-flowering daughter fan supplied resources to the flowering parent fan that allowed it to produce more buds, flowers, etc.

In a separate version of the test the double fan divisions would have larger crowns and root systems than the single fan divisions. In this version of the test the question would be whether the leaves and roots of the daughter fan supplied resources to the flowering parent fan and would include the possibility that the daughter crown tissue also supplied resources to the flowering parent that allowed it to produce more buds, flowers, etc.

Now the question is how does all this relate to the scape density? Is it normal for plants with a high scape density to tend to have a high bud count and be top branched?

I did not think nor expect that a simple mention of an active - but not widespread term - 'High Scape Density' (HSD) - would generate this much attention, interest, & concern. Consequently, witnessing the various comments, I felt obliged to give this term some additional thought. ... I was - still am - pretty certain that I know what it means. Certainly for myself. Certainly for the few growers/breeders I've discussed the term with over my years. However, how to explain this understanding now to others? Sooooo .....

Our interests with hemerocallis ... Daylilies .... can be simple for some, complex for others. I purposely mention both terms as we have among us very science minded (Training, depth + breadth of interest, metrics, etc.) and superficial (NOT pejorative. Referring to the many who simply want a "nice pink with a long bloom season that grows this high")

I explain this point of view because we measure bud counts, scape height, bloom diameter & spider definitions with given, specific references plus graphics & clear metrics. ... There exists a quite specific determination of what a 'branch' actually is (AND is not.) .

Whereas we do not have a numerical specific for what defines a 'clump' for instance. (What does "Vigorous clump development" actually mean precisely?) ....Similarly we have a variable (Flexible?) measure for EE vs E vs EM vs M vs.ML vs L vs VL. Plus - the relevant calendar dates are dependent upon latitude & local climate - even micro climates. Additionally find me specific metrics to clarify 'Great substance! .... or "Has a richer feminine pink colour than most" (OK, OK ... There are those published UK colour charts}

Well, HSD falls into the latter category in my opinion. It is a subjective, empirical quantity. A personal judgement "That those in the know, know." There is no defined number of scapes per square foot or per 'so many fans' - not that I'm aware of, anyway.

Adman Maurice (He & Sue Bergeron I consider our 'resident science gurus' for this forum.) is perhaps on the right track attempting to find specifics to define or to measure. One condition he touched upon 'synchronized blooming' could be relevant. However, my acceptance of the term is not confined by the majority of blooms opening at any given time. (Zettek DOES describe one characteristic as "Open at the same time.") It IS determined by a relatively high number of scapes existing in a given clump. (Brian Reeder uses the description "Optimum scape density.") Even with somewhat scattered bloom over time. (Growing here - PEACH MAGNOLIA - I consider HSD but it is not bloom synchronized.).

I'm content to say that it is subjective, a personal acceptance of a satisfying greater number of scapes than average, & thus blooms, than many - most? - other cultivars.

The cultivar database in this forum has many clump photos (NOT the AHS database) Should you wish to look for examples go to PRECIOUS DAUGHTER + HYPERION + DIXIELAND FIVE + CREATURE OF THE NIGHT + GABRIEL'S WEATERVANE + CORAL MAJORITY .... On the other hand, ROYAL OCCASSION & GENTLE SHERHERD are NOT HSD cultivars both in the photos & as grown here at my place.

SEEDFORK .... From my perspective HSD is not determined or influenced by bud-count or branching or 'top-branching' or "down in the foliage' or scape height .... .

It is an individual appreciation - subjective opinion - of higher than usual - higher than normal - higher than average - number of scapes up on any given clump at that time. (All 3 are vague relative descriptions) ..... It also means that such performance is expected, is repeated over the seasons, is reliable. (A 'one-season' surge in scape production does NOT necessarily draw the HSD label.

HSD is simply one of the performance characteristics to be considered. I certainly think that HSD is NOT just a genetic characteristic but is also very likely influenced by the variables of husbandry, location, etc. A good example is the previously mentioned GENTLE SHEPHERD consider NOT HSD by me. Growing here it certainly is not for a couple of decades so far. BUT in one of the Forum clump photos it could be argued that it IS clearly HSD - ???

I for one - at this point - have concluded that one cannot put this concept of HSD into any given box. It is an opinion. A judgment based upon personal preferences and experiences.(ADMAN might surprise us with some specifics the way he examines such aspects)

I recall many years ago reading that there were well over 100 factors to the analysis of any given daylily seedling being considered for registration & introduction. Some are hard measurable factual aspects (Yes? or No?) Some are opinion which is subjective. ALL are relevant for consideration. Some have a higher importance than others. Some are only important to a few others. .... Our chosen plant is complex and interesting.

So I went and looked at the photos of 'Gentle Shepherd' and I think Frank's photo definitely qualifies as having scape density!
@Wildbirds ,
Now I think I get it, that was the type of explanation (at my level) I was hoping to get. I think most of us can pretty well look at a clump and decide if it meets our unofficial definition of scape density now, and I realize now that it has a lot to do not only with the plant, but with the person growing the plant.

Seedfork said:I have mentioned scape density and it has been mentioned by others in a few threads. It was asked if there were a thread about it here on the forum,
...
I would love to get feedback in the form of actual plant experience but also any articles are research about it. I know that it relates to plants that put out a lot of scapes, compared to plants of similar size and age.
...
How to you find these plants, what are the pros and cons? Do the plants stress themselves by producing more scapes and become weak after just a few years? Are there signs to look for in new plants that would be a tip off that the plant might process this trait? Any feedback appreciated!

Larry @Seedfork, thank you for starting this thread! I think this is an important trait especially for landscape and garden value, as opposed to curiosity, novelty, or other traits collectors understandably find desirable, as they can certainly be exciting!

We can't assess this trait if the hybridizer introducing a new cultivar provides only a closeup of an individual flower.

You've already had some interesting responses, which is terrific! I hope we'll see more posts giving examples of specific daylilies exhibiting high scape density as seen in their own gardens!

There are so many different responses I'm going to reply to some individually.

In answer to one of your questions (in my experience), the cultivars which I consider to exhibit high scape density in my garden do not exhaust themselves by doing this each year. It depends on the weather to some extent. If they are stressed the number of buds per scape is likely to diminish first. Next the scape height will be less on average. Only some sort of severe stress would completely prevent them from producing scapes.

Where examined, daylilies have usually been found to initiate their first scapes during the fall and winter. If the plant (roots and crown, primarily) does not have sufficient resources, a scape may not be initiated. At that point the plant is set to flower unless something interferes.

The 2 most likely impediments so far as I know would be winter kill (the immature scapes are probably less hardy than the crown) or spring sickness. Severe drought very early in the growing season might cause them to abort early. That's not an event likely to occur in most places where daylilies are growing naturally, and gardeners in dry climates usually irrigate them.

I think there may be signs that indicate which daylilies are more like to produce high scape density, but I'll have to think about it some more. Perhaps gardeners who have grown large numbers of seedlings will share their experiences.

Pat

admmad said:@Seedfork Classifying daylily clumps by scape density implies that the flowering time of different fans/ramets in the clump will be more or less synchronized. Different fans/ramets in a clump are most likely different sizes and ages. I assume that something, synchronizes the flowering of different sized fans/ramets (that are above the minimum size for flowering or that are reproductively mature). I assume that is caused by periods of time when active growth stops either because of low temperatures or high temperatures. Scape density will presumably be lower at any given time if the flowering of different fans/ramets in a clump is not synchronized.
...
Are there locations were daylilies are grown and each episode of flowering of each cultivar is spread out over longer periods (not as well synchronized) as in other locations (better synchronized)?

Hi Maurice @admmad,
This is an interesting aspect of the topic. My experience and observations suggest that synchronization happens "automatically" with the first flush of scapes each year in my climate (USDA 6a, winter low temps averaging 0°F = about -18°C).

The scapes of deciduous daylilies emerge in each clump rather uniformly and often each have their first flower with 2-4 days. I say "deciduous" daylilies although I don't actually keep track of each cultivar in my garden as to its actual (not as claimed in registration) behavior here. So I should perhaps omit that word because I don't see any noticeable difference during the summer - all of them generally seem synchronized during the first flush.

The only scapes not synchronized here would be rebloom scapes and scapes from fans impacted by Spring Sickness. I haven't tried to record timing and spacing of rebloom here. Rebloom is generally erratic and not guaranteed.

In established clumps, I do not observe what would appear to be fans of different sizes and ages in the centers of the clumps, with the possible exception of prolific increasers with small fans making it difficult to observe individual ones, such as 'Stella de Oro'.

Generally, the fans of each clump are each spaced at a uniform distance in the central area and are uniform in size. I think that once established each fan (ramet) maintains its position and actually might be potentially immortal provided its cultural conditions do not change. I've observed a lot of variation among cultivars in fan spacing. If I do my "share" I clean dead foliage and scapes from about 1,000 clumps each spring and I am always a little fascinated by this. Maybe someday I'll take time to measure a few but in the spring the pressure is on to clean those beds as fast as possible! This year we were delayed by uncooperative March weather. 😟

Speaking of pressure I need to get back to work out there. I'll have to return to this later.

Next I'll gab about how the fans increase in the clumps.

Pat

Interesting how your scapes seem to appear at the same time and be the same size. I often see three stages of scapes of different sizes in some of my clumps.

Seedfork said:Interesting how your scapes seem to appear at the same time and be the same size. I often see three stages of scapes of different sizes in some of my clumps.

Larry @Seedfork
That's very interesting too! Obviously this is one of the benefits of a forum like this!

I see you are in zone 8b whereas I am in 6a. Much colder, shorter season here. No orange trees but we have apples. 😄 I would only see scapes of 3 different ages in some reblooming cultivars. (I did say "first flush of scapes? Should have. Often the first set is the only one here 😟). Many more probably rebloom there.

Maybe we can compare performance of the same cultivar in our gardens. Maybe others would too!! I don't have a "Have" list entered and have no idea when I'll have time to do that this time of year. I'll check your list, if you have one, to see what I also grow.

I only offer my own observations for consideration. I'm always interested in hearing others' observations.

Thanks for sharing!

Pat

Hortaholic,
Yes, I do have a have list of all the daylilies I grow listed here, just broke the 400 registered cultivar mark recently. Now I really do have to pull something out of the garden every time I add something. Most of my plants will obviously be evergreens, but I do grow over 70 dormants and some semi-evergreens. We do have a plant of the day feature on here, where people can make comments about the plants they grow. Ever so often jon and Becky ask for a list of 10 or 20 plants to include in the plant of the day. I need to do a better job of keeping up with stats!!!

admmad said:This is from the abstract of research on a species of grass,
"Vegetative ramets translocated their own resources to the connected reproductive ramets,... " <snip>

If a similar situation occurs in daylilies.... <snip>.

Maurice @admmad,

I meant to thank you in my previous post for sharing your very interesting observations of 'Stella de Oro' grown indoors continuously for 19 months. I'm looking forward to hearing more as that progresses! I snipped it because it wasn't applicable to the outdoor observations I was reporting

That's a very interesting research study of the interaction of reproductive and vegetative shoots of a grass.

I do not think the situation is comparable in daylilies in established clumps.

When I divide an established clump (several years old) I typically (with exceptions such as SS and sometimes vole damage) find that each fan in the clump has by then become an independent organism. Each crown has its own root system. There is only one terminal meristem and one fan of leaves per crown. That is why I can pry them apart into single fan plants if I want. I can't remember encountering any interior fans with dual-foliage-fans on a single crown (with exceptions as noted above).

I do not see any increase fans developing in the center of a clump. Competition from surrounding ramets apparently prevents that.

There may be cases where this competition does not prevent attempts at increase. The result would be intensified competition within the clump. That would tend to produce a clump with few or no scapes, the fans lacking the resources to flower. Maybe this explains some cultivars which have large clumps of foliage and few scapes. Old 'Orangeman' gives that appearance, but given most of the scapes are shorter than the foliage I'd have to look more closely.

Here, it appears that increase fans are only produced by fans (individuals) on the perimeter of the clump. As you know given your scholarly studies, plants have ways of detecting the directions in which they have opportunities to expand.

Eventually, increase fans end up at approximately the same distance from the parent fan/crown as the others in the clump. We don't have any solid experimental observations (that I'm aware of) which determine how it is that the increase fans become detached from the parent crown.

Some cultivars produce rhizomes. In these the spacing of the new crown is often determined by the length of the rhizome. Around the clump of 'Rosalind' there is a small flock of these fans, all spaced about 15 cm apart. But there is also a central, tighter clump which was the point of origin. In between, there are some smaller clumps. It appears that the fans that arise at a distance at the tips of the rhizomes begin to divide eventually. I haven't actually mapped this, starting with one fan as the origin. That could be informative. If only I had eternal time and infinite energy!

That's all for tonight probably. That's a relief, eh?

Maurice, you can spin out more ideas in 2 or 3 posts than I can think through and reply to in 10 - each!

Pat

When I divide an established clump (several years old) I typically (with exceptions such as SS and sometimes vole damage) find that each fan in the clump has by then become an independent organism. Each crown has its own root system. There is only one terminal meristem and one fan of leaves per crown. That is why I can pry them apart into single fan plants if I want. I can't remember encountering any interior fans with dual-foliage-fans on a single crown (with exceptions as noted above).

Interesting. Others have indicated the same thing. However, in my conditions I find that I usually have to physically cut the crowns to separate fans/ramets, very few fans/ramets are already independent. I think I once did have a daylily that had separate ramets but I cannot remember its name (if it had one - as it could have been a seedling). 'Europa' may fall apart - but I dug its fans/ramets from the outer edge of an enormous ancient patch.

I divided ten or so clumps of daylilies about a week ago. Most were to be replanted and I had to cut the crowns. I had intended to replant two fan (of leaves) divisions but most of the divisions were larger because I did not want to cut the crowns into small pieces. Four or more of the clumps were to be discarded. Their crowns were sliced with the spade. Most of the slices were as large and about as wide/thick as my hand. Most of the clumps were at least 15 years old.