'Thrive!' Drive

'Thrive!', a healthy descendent of the 'Knock Out'® rose, is a new landscape type rose that is being introduced by Star Roses in 2012.  The 17 'Thrive!' roses lining our driveway were planted earlier this year.  The photos in this post were taken today, July 30, 2011, in Bakersfield, California.  I am pleased with how it is performing despite the usual hot summer weather that we have been having.

The parentage of 'Thrive!' is ('Marmalade Skies' X 'Baby Love') X 'Home Run'.  This variety has excellent disease resistance in Bakersfield, to the powdery mildew and blackspot prevalent here, and has good disease resistance in other locations tested, getting some blackspot on the East Coast, but still holding onto most of its foliage.

The foliage and blooms are nicer during the spring bloom cycle, but IMHO it's not doing too badly now either.

The Hulthemia Holy Grail - Blotch Heat Stability

When breeding for Hulthemia hybrids, it is the blotch that is the focus of one's attention.  Seedlings lacking blotches, or those having smaller or more faint blotches are quickly looked over when a bolder, larger blotch catches the eye.  Selecting for those seedlings only, that have the eye popping blotch, results in very few seedlings that remain after the initial culling process is complete.

It can be quite disappointing therefore when the blotches "disappear" on many of these select few seedlings.  Unfortunately, that happens quite frequently.

Both of the above seedlings had good to excellent blotches when they first bloomed earlier this year as new seedlings.  Notes on their markers indicate comments like "great blotch", or "wow".  As can be seen currently, however, there is nothing "wow" about either of these two seedlings (the same can be said for most of the other "select few").

I am convinced now that the condition that contributes most to blotch fading is the higher nighttime minimum temperatures present during the summer months.  Initially, I had thought that maybe it was the greater light intensity or hotter daytime temperatures that were the cause for the blotch "disappearance".  Over the last few years though I have noted that good blotches typically return in October.  That has been true even when the daytime temperatures in October have been over 100º F (unfortunately not a rare occurrence in Bakersfield).  In October, despite high daytime temperatures, nighttime temperatures usually drop into the mid-60's or lower.  It appears then, that sustained nighttime temperatures above 70º F have the greatest effect on blotch fade, and the higher the temperature the more important the impact.

'Eyeconic™ Lemonade', as seen below in a photo taken today, has some degree of fade, but it is not as pronounced as in the seedlings in the photos above.  'Eyeconic™ Lemonade' has been useful in producing other nice yellow Hulthemias, some of which seem to exhibit good heat stability.

The seedlings in the following photos are all exhibiting improved heat stability.  These will be used heavily in future breeding while I continue to search for the Hulthemia Holy Grail.

All of the photos in this post were taken on July 23, 2011, after having warm summer-type weather in Bakersfield, California.

Informal Floribundas

The first rose depicted below is not a Hulthemia.  It is one of my favorite informal floribunda type seedlings for our area.  It blooms profusely and doesn't get any powdery mildew.  Unfortunately, it does get blackspot.  The other disappointment is that while it blooms profusely and sets hips well, the germination rate is close to ZERO.

It's parentage is [('Marmalade Skies' X 'Baby Love') X ('Stainless Steel' X 'Baby Love')] X 'Julia Child'.

---

The next seedling is new this year and is a Hulthemia.  There are several from this cross that have many petalled informal type blooms that are showing a hint of the Hulthemia blotch at the base of their petals.  My favorite is a larger pink one, but I don't have any photos of it yet.

This one is from a cross of [('Marmalade Skies' X 'Baby Love') x 'Julia Child'] X [({[('Orangeade' X 'Abraham Darby') X 'Midnight Blue'] X ('Geisha' X 'Baby Love')} X {[('Orangeade' X 'Abraham Darby') X 'Midnight Blue'] X 'Persian Sunset'}) X "mixed Hulthemia pollen"].

And it's fragrant.

The Hulthemia Line

The Hulthemia blotch has fascinated many of us ever since Harkness and Cocker released their first hybrids.  In this post, I wanted to highlight something else that I am seeing in the Hulthemia hybrids - it is the Hulthemia line.

In several of the newer seedlings, I am seeing what appears to be an alternate representation of the blotch into what looks more like a line than a blotch.  Some of the seedlings are still showing a blotch at the base of their petals, however, others are just exhibiting a darker line down the center of their petals without any other evidence of the blotch.

I suspect that this line, through subsequent generations of selective breeding, can be darkened and emphasized.  Do you think that it is worth pursuing?!

'First Impression' Proving To Be Quite Clean

This is a short departure from writing about the new Hulthemias, to write about an older seedling.  With this post, I wanted to highlight the disease resistance that I am seeing in a seedling from 6 years ago that has been named 'First Impression'.  'First Impression' is a dark yellow floribunda, introduced by Nor'East, and now carried by Greenheart Farms.  It has surprisingly good disease resistance - especially in our climate, but I am getting good reports from other areas of the country too.

The photo above was taken with my iPhone during a trip to Greenheart earlier this year.  I took a video of the plant (unfortunately after its peak bloom) to show its disease resistance in our non-sprayed rose garden.  Click here to see the video.  'First Impression' is the second rose in the video and has all of its foliage.  The first rose is heavily defoliated, while the third rose (actually a fairly clean rose too) has several leaves showing blackspot.  'First Impression' doesn't have a single blackspot on it.  For those interested in breeding yellow roses, I would suggest using this one.  There haven't been a lot of hips on 'First Impression' in my experience, but for some reason, most of our roses have produced an abundance of OP hips this year including 'First Impression.  I would mainly use it as a pollen parent, but who knows, maybe you could also get lucky and get good hips on it too!

'First Impression' came from a cross of [('Lynn Anderson' X 'Tournament of Roses') X 'Hot Tamale'] X ('Stainless Steel' X 'Baby Love').  Other than from 'Baby Love', I am not sure where it is getting its good disease resistance.

A Brief Study of Hulthemia Petal Color Distribution

For anyone already reading this blog, it is clear that the characteristic defining difference between regular roses and Hulthemia rose hybrids is the darker blotch seen at the base of the petals in the Hulthemia hybrids.  The blotch though, has several variations, all of which have the potential for offering new distributions of color on rose petals.

Several different distributions of color can be seen in the photo below.  This is by no means a complete representation of the various color distributions that are possible with the Hulthemia hybrids, but it does show a range of the possibilities.

All of these have at least a hint of the blotch, but on closer look, it can be seen that besides the obvious difference in color of the petals, there are also different distributions of the blotch color and accompanying petal coloration patterns.  To more easily discuss these differences, I have repeated the above photo of Hulthemia petals with numbers attached to each of the petals and copied it below.

Probably the most classic representation of the blotch is seen in petal 19.  There is a good solid blotch that goes all the way to the base of the petal and it has a distinct outer edge about 1/3 of the way to the petal edge.

Variations on this pattern include those with a lighter coloring just outside the blotch zone.  The lighter color really helps to accentuate the blotch.  Examples of this variation are petals 6, 9, 10, 13, 14, 16, 18 and 21.   You might include petal 7 in this group, and you would probably be right.  I think it is a bit different though because it also has a fairly larger separation from the blotch and the petal base.  The blotch that remains is barely visible, but it is there.  Others that have a "cut-off" zone of the blotch from the petal base include petals 1, 5, 6, 13, 14, 15, 16, 17, 21, 24, and 25.  You might throw in a few others with more subtle "cut offs".  This effect is less noticeable on more mature seedlings.

Another variation is a kind of "streaking" of the blotch out to most of the rest of the petal.  Examples of this pattern can be seen in petals 3, 5, 17, 22, and 25.  Not seen in these examples is another more gradual blending of the blotch as it fades (rather than "streaks") out further on the petal. This can be seen in the photo below of petals from J93-3.

Finally, some of the petals are showing more of the blotch going outward along the center of the petals simulating the appearance of a "line" (I will mention more about this in a later post), examples include petals 1, 3, 5, and 11.

For the fun of it, I included petal 23 in this photo.  As seen in an earlier post, it is possible to combine striping with the blotch.

The last 2 photos show the streaking effect in better detail.  In these seedlings the blotch is not as dramatic as in the more classic type Hulthemia blotch.

Hulthemia Petals - Front and Back

Here are more Hulthemia petals coming from some of the new 2011 seedlings.

As is seen above, the reverse is almost always lighter than the top side of the petal.  Additionally, I have never seen the blotch pigment on the reverse side.  I am hoping that it will be possible though, so will continue to keep my eyes opened for it!  I think that a reverse blotch would be especially nice on otherwise typical exhibition type blooms.

The Effect of Petal Count on Hulthemia Bloom Presentation

Just like regular roses, Hulthemias come in all types of bloom forms - there are singles, to semidoubles, all the way up to hundred petal types.  In working with these, I have seen that the single petal blooms, those having 5 petals, provide the clearest, unobstructed view of the blotch.

While those with many petals, can hide the blotch altogether.

In these, the blotch is only visible by removing the petals.

For me, the most attractive presentation of the blotch is seen in semidouble style blooms, where there are only 10 to 20 petals.

What do you think?

Hulthemia with Unusually Shaped Petals

This seedling was a happy surprise!  It's always a special treat getting something that I have never seen before. It's like finding a different, but pleasant flavor in a box of chocolates that you have never tasted. The petal shape reminds me of a chrysanthemum.  So far the plant appears to be quite clean (no powdery mildew), and since it has a good blotch, it will probably be a "keeper" among this years new seedlings.

What do you think?

The Tiniest Hulthemia

This is by far the smallest Hulthemia seedling that I have grown.  The height of the plant is not as tall as the thickness of my hand.  There are two open blooms, a third bloom opening, and a 4th bud about to open.  I cannot yet tell whether or not there will be a blotch.  Even so, just for the sake of it's novelty, I will continue to watch this one as long as it survives. At least it won't take up that much extra room!

The Hulthemia in the Striped Pajamas

This seedling, code named N210-1, sprouted last year.  It came from a batch of "OP" seeds from one of my earlier repeat blooming Hulthemias.  I have no idea what the pollen parent was, but clearly, this was not the result of a self pollination.  I had been trying for the two previous years to come up with a striped Hulthemia, and though I got a couple of them, neither was as good as this one.

It appears to have a plant habit and quantity of bloom similar to 'Ballerina'.  It has a couple of real bonuses too: it seems to be one of my cleanest Hulthemia seedlings, and it has an abundance of pollen, making it ideal for use in further breeding).  As expected, it has been put to work quite a lot this year.

P.S. This idea was inspired independently by my daughter Claire, who was 10 years old at the time, and by my favorite mentor in rose breeding, Mr. Ralph Moore (forever young at heart), who was 100 years old at the time!

A Most Remarkable Blotch

Among the new 2011 seedlings today, I had the opportunity to encounter one of the most intense blotches that I have seen thus far in the Hulthemia hybrids.  The petal color on this seedling, code named "O343", is a light cream, with a fairly large, deeply maroon blotch.

As with other very dark rose seedlings, it is possible that this blotch will burn in full sunlight.  Even so, the size and intensity of this seedling's blotch destine it to become an important parent for future generations.

---

Previous experience has shown that blotch size increases with maturity.  Up until now, the Hulthemia seedling with the largest, most intense blotch has been M40-1.  In the photos below it is easy to appreciate the change of the blotch as seen in the first immature bloom to that of the more mature plant grown outside.

Of note, the seedling at the top of this post, "O343", was the result of a cross made between two new seedlings from 2010. Using superior immature Hulthemia hybrid seedlings in crosses during their first year, has helped to shorten generation time and has produced some good results.

Peak Bloom at the Sproul Rose Farm

The warmer weather has brought on the peak bloom rather quickly.  Approximately 1/3 of the 1,000 potted roses seen here are new 2010 rose seedlings that were brought outside the greenhouse for further evaluation.  They survived scrutiny in the greenhouse where more than 95% of the 2010 seedling roses were eliminated.  The rest of these are seedling roses from previous years.

My goal over the next few weeks will be to cull out 1/3 to 1/2 of these, so that only the best of the best remain.  We were fortunate to get just the right amount of downy mildew this year - not so much that the seedlings lost all their leaves, but enough to differentiate the resistant ones from the susceptible ones.  Also, keeping the pots jammed rather closely together has helped to promote blackspot.  All of this has provided a better opportunity to get a much better read on which roses are performing the best with respect to disease resistance to downy mildew, blackspot and powdery mildew.  Some of the roses are spotless.  It is from these that I would like to carry the breeding program forward.

More Hulthemia Blooms

The first 3 photos below are of more 2011 Hulthemias.  The last 2 are photos of two Hulthemias from 2010 that are blooming for the first time outside of the greenhouse.

The first seedling pictured below bloomed a few days ago, while the second one bloomed today.

The last photo of the 2011 Hulthemias, is of petals from the best striped Hulthemia to show up so far.

---

Next, are photos of the 2010 Hulthemias blooming for the first time outside of the greenhouse.

The first one is of a mini single.  It stays very compact and seems to put on a good bloom display.

The last Hulthemia pictured below appears to be a spreading shrub type.  The blotch eye-zone is quite distinct and with good saturation of the blotch coloring.

Hulthemia Petals - New and Old

Today, there were many new seedlings blooming for the first time necessitating much culling.  There were many Hulthemias that had to be culled today, and many more that will be culled in the next few weeks as the seedling greenhouse explodes in color with new blooms on new seedlings.  In the first photo below, you can see the Hulthemia seedlings that didn't make the cut.  Each petal represents an individual seedling.  As can be seen, many of the petals are similar.  If plants and blooms were seen, the differences between seedlings would be easier to appreciate.  The petal/blotch represent just one trait of interest in determining which seedlings to discard, and which to keep.

The next photo represents petal for petal, surviving Hulthemia seedlings that bloomed today.  Of course it remains to be seen which will be more floriferous and which will have greater cleanliness, so it is possible that ultimately none of these will survive.  For now however, they continue to grow in the greenhouse seedling beds.

The final photo in this post is of petals of Hulthemias that have survived the test of time.  These represent some of the best that have grown in our greenhouse over the last 5 years.  From these, pollen was harvested that will be used tomorrow in crosses with the objective of developing still better Hulthemias.  One of the petals below comes from a new Hulthemia that is being introduced by Star Roses that is being named 'Eyeconic™ Lemonade'.  Some of the others are still under evaluation.

Two Better 2011 Hulthemias

The two Hulthemia seedlings that I will highlight in this post are more interesting to me than the previous two seedlings that I have been writing about.  These two, exhibit very good blotches despite this being their first blooms.  As mentioned earlier, with maturity blotches increase both in size and in intensity

The first one, code name "O225" appears to be a smaller shrub type.  It's pollen parent is one of my favorite earlier Hulthemias carrying the code name "M62-1".  It was one of the best Hulthemias that germinated in 2009.  Unfortunately, it has very low fertility, therefore I was quite pleased to get a few hips from crosses done with it last year (most of the crosses failed).  The seed parent was 'Pearl Sanford'.  This new seedling shows more evidence that when a repeat blooming (presumably tetraploid) Hulthemia that has an excellent blotch (presumably having more than one copy of the blotch gene(s)), is crossed with a non-Hulthemia, it is still possible to get a good blotch.

As seen in this seedling, I prefer Hulthemias that have a lighter area around the blotch because it sets off the blotch very nicely.  It is harder to appreciate the blotch in seedlings that do not do this - as will be seen in the next seedling.

The next seedling is very unusual, and it appears to be a micromini.  This is the first time that I have had such a small Hulthemia seedling showing such a dark blotch on it's first bloom.  It comes from a complex line, where the seed parent has 'Persian Sunset' in it's background, while the specific pollen parent is unknown (I used mixed pollen from seedlings coming from a cross of 'Cal Poly' X "L83-4").  L83-4 is a cream colored Hulthemia having a fairly larger purple/red blotch.

In the above photo, it is difficult to appreciate the size of the blotch, or even the size of the seedling bloom.  The blotch is even more difficult to appreciate due to the color of the anthers.  They are unusual in that they are a deep red.  For that reason, in the following photo, I removed the anthers and used a centimeter measuring stick to provide better clarity.

As you can see, the bloom is very small, and with the anthers removed, it is much easier to appreciate the blotch.

To be complete, I also removed the anthers from the first seedling and present a photo of it below:

Not knowing whether either of these will be fertile, I have collected the anthers of both and will use their mixed pollen in crosses onto some of my Hulthemia seed parents over the next two days.  I have learned from experience that many of the Hulthemias with the best blotches seem to have lower fertility - that is why I like to mix their pollen.  Curiously, although the bloom size difference between these two seedlings is quite large, the anthers appear to be approximately the same size.

2011 Seedling Update - Seedlings Blooming!

Well the two seedlings that we have been watching have bloomed!  Neither one is very impressive.  The first seedling does turn out to be a Hulthemia, although you cannot tell readily by just looking at the bloom.  If you do look carefully though, you may notice a small blotch at the base of the petals. 

It is much easier however, to distinguish the blotch after the petals have been removed.  Smaller blotches tend to get hidden by the anthers.

The lighter petal reverse seen on this seedling is characteristic of most of the Hulthemias.  In my experience, the blotch has always been present only on the upper surface of the petals.  This is different from the "Halo" roses produced by Mr. Ralph Moore, where the darker coloring of the halo often shows through to the reverse side of the petals.

Although the blotch is quite small in this brand new seedling, it will be significantly larger in the mature plant.  Generally speaking, the blotch gets about 3 times larger and with deeper coloring in the second Spring bloom.

Additionally, this seedling may have too many petals.  In the first blooms there are at least 15 petals.  I would expect 5-10 more petals in a fully mature bloom.  Blooms having 20-25 petals or more will not allow the blotch to be presented in the most attractive way.

I have decided not to discard this one yet.  I do like the vigor of the plant and so far it appears clean.  There is very little powdery mildew in the greenhouse at this time, but it will soon be here in full force to help differentiate which seedlings to keep and which seedlings to discard.  If this one gets powdery mildew, it will be culled.

---

The second seedling is clearly a single like the pollen parent.  The red coloring is somewhat washed out.  It's only redeeming qualities are sturdiness, well branched habit and possible good blooming power. The buds to the left and right of the open bloom belong to this second seedling.

This seedling will most likely be discarded, however, I have decided to watch it a bit longer to see what the next bloom cycle looks like.  As with the first seedling, if this seedling gets powdery mildew, it will be culled.