I am a day lily amateur. I grew day lilies in Atlanta years back and the colors stayed the same year after year.

Two years ago I purchased a house in Baltimore area with a overgrown garden (most good plants removed while in probate).

Anyway the day lilies still in the garden had a heavy dark yellow gold color. I moved them to the back yard and ordered and planted day lily varieties in the cherry and pink colors - about 12 different varieties - in the front. In the back I added some lovely orange to go with the existing dark yellow gold.

Everything came up roses last year. Bright cherries and pinks and white/purple contrasts This year all the colors have more of a dark cast to them and the bicolor have less contrast. Even the one Bitsy I put because was my garden edge favorite in Atlanta is a dark yellow this year.

I am not hallucinating - it isn't a camera or a cloudy day issue - as it is ALL of them. BTW - the oranges in the back gardens are spectacular = so it is impacting them also.

Soil is heavy clay I've amended with garden soil - and the street was built on an old stream bed in the 50s (yes go figure).

Is this a permanent thing or something that can be alleviated with a soil amendment? Azaleas, quince, and lilies still here from the prior owner who was a master gardener are orange. So maybe she knew something?

Any and all advise welcome.

@HeckYes.
I'm here in Baltimore too. Weather can play a big role in how my daylilies appear with darker colors in the cooler weather. It has been cooler here the last few days with crisper night temps. I would be curious as we are now getting some warmer temps if you notice lighter colored blooms.

I would look at differences in the amount of sun/shade and temperature (microclimate) first. If you still suspect it is soil related you might want to get a soil test, better yet a separate test for the two different areas. Some people will likely say Epsom salts helps (that could be relevant if the soil lacked magnesium but extra magnesium when it is already adequate in the soil naturally shouldn't make any difference) others might say soil pH makes a difference, but I don't know of any blanket recommendation as a one size fits all.

@HeckYes,
to the forum.
I have some years when some blooms look outstanding and the colors just pop. Other years those blooms don't look so nice but other plants in the garden produce outstanding blooms. So even here the colors are not always consistent with all the daylilies, but I don't recall having a year when all the colors seemed to shift. So I have no answer for you. Maybe it is just the cooler weather as Jill suggested.

If you can see Figure 1 from this article, it shows that pigment concentration varies with different temperatures:
https://www.researchgate.net/p...
The article is probably a little too detailed for us.

The figure below and the photographs of the chrysanthemum flowers show how temperature affects flower colour. What happens in other flowers, such as chrysanthemums also happens in daylilies.

The higher the temperature (above the optimum) the less pigment (the lighter the colour). The lower the temperature (above the optimum) the more pigment. Sunny days versus cloudy days (if there are enough of them) also change the amount of pigment.

Case in point for heat causing washed-out blooms:
Opting Out last June 17 (overnight low 57°F, daytime high 70°F)
Opting Out last July 2 (overnight low 68°F, daytime high 88°F)
Opting Out FFO today (overnight low 72°F, daytime high 90°F)

Thanks everyone. Let's keep going to solve this mystery.

I've had daylilys in my gardens for nearly 20 years now. Yes - rain amount and sun and temps can impact colors. I agree those kind of changing conditions morph the flowers to make the same color stronger or fade it to lighter.
I purposely put some colors in partial sun vs full sun and you'll find me out there watering when the days get too dry. But never has the whole garden array of pinks morph to more orange. (yes, I am that gardening crazy lady down the road!)

I noticed in the post purchase reviews on the daylily sites once in a long while someone would complain that in their garden the darn thing turned more orange (as a negative comment/blaming the seller for misrepresenting picture). SO I figure there is something going on. No amount of google searching would find the answer - - - so I've turned to you guys- the "on the ground" experts. Need to get to the bottom of this and post the answer.

Yes - soil test is next. Also suspect there is an impact between rain and hand watering, so maybe too acid?

Attached pic of some awesome oranges - and one that should be cream and purple....

admmad said:....What happens in other flowers, such as chrysanthemums also happens in daylilies.
...
The higher the temperature (above the optimum) the less pigment (the lighter the colour). The lower the temperature (above the optimum) the more pigment....

I can not agree fully to this opinion - it depends on the cultivar.
Some daylilies need heat to show intensive colors - best examples in my garden are Dakar, Rolling Raven and Black Pearl

Cold temperatures:







Warm temperatures:







I have other dark cultivars in my garden that suffer from heat and look ugly.

This color intensifying effect can be seen on some lighter colored ones too - best example here is Ursula Heuss (German cultivar, bread in colder climate):

Cold temperatures


Warm temperatures


I bought the cultivar for its clear light colors - as we usually have warm temperatures here the plant looked muddy everyday - so I gave it to a friend in alpine climate where it is beautiful pale.

So my conclusion is - temperature may cause paler flowers but the opposite is possible too.

There is nearly always genetic variability in anything measured or observed. Different cultivars can have different optimum temperatures and they can have different rates of change below or above the optima. However, temperature is not the only factor that affects anthocyanins. So does the amount of sunlight. As well there are different anthocyanin pigments and factors such as temperature and sunshine may affect each type of pigment differently (the optima can be different and the rates of change above and below the optima can be different). Many daylily flowers contain several types of anthocyanin pigments as well as other pigments in the flavonoid pigment pathway that can change the colour of the anthocyanins. They may be affected by light and temperature with different optima and rates of change.

In the graph the maximum amount of pigment is at about the temperature at B. At the warmer than optimum temperature E there is more pigment than at the cooler than optimum temperature A. On the other hand at the cooler than optimum temperature C there is more pigment than at the warmer than optimum temperature G. The relationship between just temperature and the amount of pigment is complicated and knowledge of the optima is required.

Below are three photos of 'Bela Lugosi' taken after different lengths of time that were cool or cloudy or both, showing how different the anthocyanin pigmentation of daylily flowers can be.



'Bela Lugosi' showing patterning caused by temperature and/or sunlight interacting with the internal environment of the petals in association with veins.

Photos of 'Midnight Magic' from different growing seasons, again after periods of cool and/or cloudy weather.



Much of the effects are caused by different pigments responding differently to the temperatures. The end results on the petal colour and patterning depends on the types of pigments and their concentrations in different locations of the petals and how those are affected differently by temperature, sunlight, etc.

Below is a high resolution close-up of a petal from 'Midnight Magic' showing some of the effects of weather conditions.

Thanks for the pics and the explanations.

My experience is: the best and brightest colors in my garden appear after a tropical night (defined in our corner of the world by temperatures of 20°C and above) with soft rainfall on an overcast morning.

But the initial question was about type of soil - up to now I have seen warm and yellowish colors on limy soil in my garden, nearly every near white is yellow, nearly every pink is peach and cold bluish colors. The opposite I've seen on acid soil in the garden of a friend, was a pinewood before turning into a daylily garden. All the yellow and peach ones I gave to him look perfect near white and true pink in his garden.

But there is a different factor in this speacial comparison - I live in a region influenced by mediterranian climate, his garden is in alpine climate.

I also have seen very pale colored daylilies around here in neighbours gardens if it's really hot and nobody waters this clumps. Most of them I grow too and compared with my plants - daily watered by an irrigation sytem - you can see significant differences.

I've noticed color changes from transplanting seedlings out of my red clay based soil to rich black dirt, the clay soil gave me richer more vibrant colors
The two seedling samples below both have more red color growing in the clay, when moved to rich black dirt they look like different plants
The first seedling grew in the clay for several years before being moved then changed color, the second seedling was moved in the fall after maiden bloom year, I like the red versions better for each

S-398 {S-214 ((Techny Peace x Caledonia) X Spacecoast Starburst)



I-334 (Angelique Fringes x 3114 (Randy Stephens x Rosy Spiketail))

@EdBurton do you happen to know if the soil pH was different between the clay and the black soil?

Sue I do not, sorry

EdBurton said:Sue I do not, sorry

I wondered because my totally unscientific observation when I was experimenting with lowering the pH due to chlorosis was that the flower colour was better on the test clumps. Since I didn't have the same cultivars split and side by side, one with lowered pH and the other not for comparison, it has to remain just an impression. I guess another thing to add to the "to do" list!

@sooby

the flower colour was better on the test clumps.

By "better" might you mean clear, or more vibrant or more intense? Might the flower colours have been different - more purplish, more reddish, deeper yellow, etc. Were there effects on cyanic colours (reds & purples) and on carotenoid colours (yellows, creams, etc.)?
Any specific cultivar names?

admmad said:@sooby

By "better" might you mean clear, or more vibrant or more intense? Might the flower colours have been different - more purplish, more reddish, deeper yellow, etc. Were there effects on cyanic colours (reds & purples) and on carotenoid colours (yellows, creams, etc.)?
Any specific cultivar names?

This is going back a long time but my recollection is that it was a clearer pink and the red eye was redder on the only cultivar I remember, 'Siloam Cinderella'. I no longer have it so can't re-do more scientifically. Lowering the pH did fix the interveinal chlorosis on the daylilies suffering from it (which turned out on analysis to be manganese deficiency caused by the pH).

sooby said: it was a clearer pink and the red eye was redder on the only cultivar I remember, 'Siloam Cinderella'. ... Lowering the pH did fix the interveinal chlorosis on the daylilies suffering from it (which turned out on analysis to be manganese deficiency caused by the pH).

Manganese has been shown to affect anthocyanin levels; I assume that a deficiency could cause colour differences in the flowers and correcting the deficiency could produce changes in the anthocyanin pigment levels.

I purchased Baby's Got Blue Eyes (not from the breeder), which Diana Gossard shows with a near white base color, but mine blooms with an orangy peach base color. You can see similar photos in the database here

https://garden.org/pics/2017-0...

https://garden.org/pics/2018-0...

Mine has all the lovely blue violet and green things going on in the center, but I am disappointed with the base color presentation. Is this soil-related?