Heat tolerance

[helixturnhelix]

To be honest, I think I got lucky picking pretty good seed setters and having some atypical weather when I did my crossing (remember when it was really cool in june/may?)  I have to say that it looks like even in this heat Belle is still setting seeds.  Saffron is cut back, but was dropping buds because of the weather so I doubt it would have set and seeds.  I think cinnamon girl and blue ballerina are  supposed to be seed setters and I know for a fact that saffron and belle du jour do.  I think I will try giving belle a break from making seed pods because now that they have all ripened except 1, and she is starting to produce many more buds.  I guess the energy that was used to make the seeds is going back to flower production.  I think maybe looking at Creme de Cacao would be a nice addition to your cv list because it is supposed to set seed and produce hot pollen.  I have seen a full Creme de Cacao bush and it is really lush and the flowers are really pretty in person.  If you like the way cinnamon girl looks, I think you will like this one too. 

I also dont know if this matters, but I didnt remove the calyx on a few crosses and I wonder it this serves to protect the seedpod a bit from the sun.  It is my understanding that usually this is removed to prevent fungus from getting into the pod, but in our hot dry weather, maybe it will form some sort of protection.  Perhaps it is something to look into

-Chris

[Nievesgirl]

To be honest, I think I got lucky picking pretty good seed setters and having some atypical weather when I did my crossing (remember when it was really cool in june/may?)  I have to say that it looks like even in this heat Belle is still setting seeds.  Saffron is cut back, but was dropping buds because of the weather so I doubt it would have set and seeds.  I think cinnamon girl and blue ballerina are  supposed to be seed setters and I know for a fact that saffron and belle du jour do.  I think I will try giving belle a break from making seed pods because now that they have all ripened except 1, and she is starting to produce many more buds.  I guess the energy that was used to make the seeds is going back to flower production.  I think maybe looking at Creme de Cacao would be a nice addition to your cv list because it is supposed to set seed and produce hot pollen.  I have seen a full Creme de Cacao bush and it is really lush and the flowers are really pretty in person.  If you like the way cinnamon girl looks, I think you will like this one too. 

I also dont know if this matters, but I didnt remove the calyx on a few crosses and I wonder it this serves to protect the seedpod a bit from the sun.  It is my understanding that usually this is removed to prevent fungus from getting into the pod, but in our hot dry weather, maybe it will form some sort of protection.  Perhaps it is something to look into

-Chris

I did the same when it was cold that was the heart hotel x voodoo it just dropped off and turned yellow after about 3 weeks in.
Its super humid 3 stories up so I figured this would help and lots of shade. Maybe like I said the fertilizer issue is the reason. 

as for the calyx you may be right, I read that it harvest inspects and I have notice this also.  i take mines off but maybe the next time I will leave it and make sure I spray bayer or hort oil to keep bugs away.

[Charlie]

One of the things that has kept me busy the last few days is working on the HVH list of cvs to register with the American Hibiscus Society. Their database, the oldest in the world for hibiscus, has been languishing in no man's land for about 4 years now. They want it to be professionally maintained instead of relying on volunteers so made a deal with LSU to be a paid provider of this service. LSU was paid but they don't seem to be able to get anyone to actually do the work so far. Even so, the guy in charge of getting the data to LSU has been writing to us and giving us a deadline for getting our data to him. That bodes well for something finally happening. My point is that with a backlog of maybe 5 years of data from American hybridizers it has been hard to research recent trends in hybridizing. Once this new database is up and running and available online it will be easier to see what people like Jill in HI have been doing.

Charlie

[Charlie]

Kerry, there are any number of reasons why it can be and usually is hard to get pods in the summer. I don't think it will turn out to be either the calyx or fertilizing. It takes fresh pollen on moist pads to start the process and if it gets too hot at any point after that the pod can still drop. BTW, never blame yourself for knocking a pod off a plant. It was going to go anyway. When a viable pod forms you can pick the entire plant up by grasping the pod. Not recommended, of course.     Seriously, they do form quite a strong bond and are not able to be knocked off casually.

As for the calyx I have seen insects inside a few times but I remove it mostly so that I can more easily spot the pod turning brown when it ripens. You only have a short time to harvest the seeds before they spill out as nature planned so it is best to see the pod turning colors and remove it then. I let the seeds finish darkening inside the pod for another day or two after picking a pod that is just starting to split open and turn brown.

Charlie

[helixturnhelix]

Random question charlie,

When you register a new cv, what are the criteria that it must pass in order to become a new registered cv?

[Charlie]

Unlike roses and some other well established species, there are no stringent requirements for hibiscus. The main one is that the name is not already in use. It is suggested that you have grown the plant for a couple of years, and have propagated it successfully, and it "should" be unique enough not to be a repeat of an existing cv. That last one is the tricky part, because if I have a flower that is similar but on a better bush I do not consider it to be "too similar".

There are also some naming conventions about length of name, offensive names, etc but as far as the qualities of the cv there is nothing expressly required.

Charlie

[helixturnhelix]

Thanks charlie for shedding some light on that

[Nievesgirl]

Kerry, there are any number of reasons why it can be and usually is hard to get pods in the summer. I don't think it will turn out to be either the calyx or fertilizing. It takes fresh pollen on moist pads to start the process and if it gets too hot at any point after that the pod can still drop. BTW, never blame yourself for knocking a pod off a plant. It was going to go anyway. When a viable pod forms you can pick the entire plant up by grasping the pod. Not recommended, of course.     Seriously, they do form quite a strong bond and are not able to be knocked off casually.
As for the calyx I have seen insects inside a few times but I remove it mostly so that I can more easily spot the pod turning brown when it ripens. You only have a short time to harvest the seeds before they spill out as nature planned so it is best to see the pod turning colors and remove it then. I let the seeds finish darkening inside the pod for another day or two after picking a pod that is just starting to split open and turn brown.

Charlie

Haha I did not know that this whole time I thought your can knock the pods off easily , I pollnate them early in the am right when they open.  The only one staying on the plant is gator pride x gator pride

[Charlie]

Yeah, I recall the anguish after appearing to knock off pods, until I learned that viable ones can't be knocked off.

CB

[Nievesgirl]

I was thinking about heat tolerant plants that came from AU. I looked at some of the pedigrees on certain AU cv's and some are just the same crosses that we have in USA. Do you think the plants are adapting to the regions climate ?

I am guessing the Au hybridizers are selecting plants that are heat tolerate ( without really thinking about it ) And this is creating more heat tolerate plants.

[Charlie]

Assessing heat tolerance by region or country is interesting, and the results somewhat surprising. As for the question of US and Australia hibiscus diverging it is indeed possible but I am not sure how much of that has happened. There has been smuggling of hibiscus cultivars between the 2 countries pretty much forever, although it is much less now then it used to be. Both countries try to protect their cotton crops from pests and diseases that are not native to the country so government regulations make it difficult to share hibiscus back and forth. HVH made the only legal exchange between the 2 countries several years ago. We swapped over 100 varieties of our best for their best which helped spread the genes around. Neither country has native hibiscus species that are part of the cross-compatible group so both have relied on imports from elsewhere (except for Hawaii but both the US mainland and Oz have imported from HI, too).

So what happens with the gene pool in each area as hybridizing continues? Just looked at from a weather perspective it is sort of interesting. Using weather.com as the source for data, I compared Fallbrook (southern California where I live), Houston, Miami, and Brisbane Australia. Brisbane is the largest city in the state of Queensland and just north of Brisbane and the same distance from the coast is Caboolture, the home of the 2 biggest hibiscus specialty nurseries in Oz. No data existed for Caboolture so I used Brisbane which I think is representative.

Both the high temperatures and the low temperatures affect hibiscus growth. The longer the temperatures remain at either extreme the more the growth and blooming are affected. Where I live in Fallbrook, about 10 miles inland from the Pacific Ocean, the high and low temperatures for the year are the closest match to Brisbane, Australia. Our average highest high for a month is 84F and our lowest low month averages 45F. Brisbane has a highest high month of 84F and lowest low month of 48F. However, this is not the whole story. Brisbane also has 5 months during which the average high is above 80F while Fallbrook has only 3 months that average above 80F. The low is even more important in some ways and Fallbrook has 6 months of the year where the average low temp is below 50F while Brisbane only has 1 month below 50F. Lots less cold stress on hibiscus in Brisbane!

It turns out that despite the average person's perception of Oz as being a very hot country, the average high temp is significantly lower than in Houston and Miami. This probably contributes to better or a longer bloom season in Oz than in TX and Florida. Houston's highest high month averages 94F while Miami has a high temp month that averages 91F, both well over Brisbane and Fallbrook who come in at 84F. Houston also has 6 months that average over 80F and Miami a whopping 9 months that are over 80F. Houston however is colder than every place but Fallbrook, having 3 months that the average low is below 50F. Miami has NO months below 50F with the coldest month averaging 60F.

So, although it is common to think of Australia as developing heat tolerant hibiscus that is not consistent with the weather facts. I think, based on anecdotal reports from Oz, that hibiscus growers there tend to plant their hibiscus in the ground rather than grow it in pots and they also tend to grow in full sun rather than provide shade for their hibiscus. With the overall rather mild weather that Brisbane has this makes sense. Sun and heat are directly related as per creating stress in hibiscus. Since it is not that hot in Brisbane the plants can take the direct sun. Since it is not that cold either, planting in the ground is not as risky as it is for many areas of the US. The cultivar Rosalind is a prime example of a good performing variety that originated in Australia. In our experience Rosalind can be grown in the ground and in full sun and does very well at least in the climate of Fallbrook.

I'd love to get some comments from Australia on this topic. How do you grow your hibiscus? How hot and cold does it get where you live?

Charlie