Is 'Sri Kembangan' carambola self-compatible for pollination?

[CoPlantNut]

I have a healthy 2.5-3-year-old 'Sri Kembangan' carambola in bloom for the past 3 weeks.  Despite my best efforts at pollinating it manually, I have zero fruit set.  I haven't tried dressing up in a yellow and black striped outfit and making a buzzing noise (yet), but I have tried everything else I can think of to pollinate it.

I have fruited smaller, younger carambola trees here before in much less-ideal conditions; why can't I get this "zucchini of the tropical fruits" (as Oscar called it) to set some fruit for me?  This is the 5th bloom flush it has had since I've had it, but I can't seem to get any fruit.  My previous "successes" with carambola were all with seedlings that met unfortunate ends in Colorado hailstorms (always just before the fruit ripened...) but I didn't have to do anything special to pollinate them.

I've had this grafted 'Sri Kembangan' for almost 2 years and despite it growing and blooming happily and being much larger than my previous fruiting carambolas, I get no fruit.  I'm manually pollinating with a small paintbrush, the plant is enjoying 15 hours of light and 65-90 degrees every day, leaves are a nice medium-dark green and aren't chlorotic, growing nicely, but every flower falls off within 48 hours of opening.

Am I missing something?  Being overly hopeful that I can get it to set fruit when 4 feet tall and wide in a 5-gallon pot with a 3/4" thick trunk?  Or is 'Sri Kembangan' simply not self-compatible?  Unfortunately, my only other carambola (and the only one I know of within 500 miles) is also a grafted 'Sri Kembangan', not blooming at the moment, but growing happily.


   Kevin

[fruitlovers]

Yes the starfruits are self pollinating. Is it protected from the wind? Those flowers are very easily knocked off in windy areas. Other possibility is that temperatures are too low during flowering for pollen to fertilize the flower.
Oscar

[CoPlantNut]

Yes the starfruits are self pollinating. Is it protected from the wind? Those flowers are very easily knocked off in windy areas. Other possibility is that temperatures are too low during flowering for pollen to fertilize the flower.
Oscar

It is experiencing only mild 'artificial wind' from a small (8") oscillating fan about 5 feet away.  Minimum temperature is 65 degrees at night; I've tried pollination when it is 70, 75, and 80 degrees (as the day progresses).  Does it need more than 80 degrees for the pollen to shed?  Humidity ranges from 65-100%.  This is in my basement, so there are no natural pollinators available.

   Kevin

[fruitlovers]

Oh, sorry Kevin, forgot you were raising inside your heated basement. Lack of pollinating insects then no doubt is the problem. Try to keep the humidity and temperature as high as you can at time when you do the hand pollination. I've never tried to hand pollinate starfruit so can't help you with that.
Just looked it up in Morton to see what the pollination mechanism is. No info on that, but she does say: "Interplanting of different strains is usually necessary to provide cross pollination and obtain the highest yields." So maybe you're right and your plant is self sterile. If you have a different plant to pollinate with try that.
Oscar

[CoPlantNut]

Unfortunately, I know of no other carambola plants in Colorado.  I really only have the space and desire to grow one carambola tree; I know most are supposed to be self-compatible and I have experienced that here in the past.

My first attempt at growing a "superior" cultivar makes me think I picked poorly with 'Sri Kembangan'!  Does anyone know of a good carambola variety that is definitely self-fertile?

   Kevin

[fruitlovers]

Is this the first time it has flowered? If so that could also be the problem. Oh i see you say it is only 3 years old. Many juvenille plants abort flowers, some kind of self protection mechanism. I wouldn't jump to conclusion it is self sterile. I say give it another year, another flowering round.
Oscar

[CoPlantNut]

Yes, I don't think I'll dump both my plants just yet.  This is the 5th time the currently-blooming plant has bloomed; it was also shipped to me in bloom but I cut all of them off when I received it.  My other 'Sri Kembangan' of identical age and similar size has bloomed 3 times since I've had it; it seems a little more reluctant.  The one in bloom at the moment has had 200-300 flowers abort so far this cycle, with probably only 100 flowers left to open.  I've never had a carambola tree flower so profusely and not set fruit, but I've only done it twice (not concurrently) in the past so I guess I was just spoiled when my previous two attempts self-pollinated and bore fruit when only 2 years old and on their 2nd or 3rd bloom cycle.

I may try to switch out one of my plants for another variety though; it can't hurt to have two varieties around and try a new one out.  I picked 'Sri Kembangan' because I'd had it fresh off the tree in Hawaii before and knew I liked it, but if it isn't self-compatible I'd rather have another variety that is.

If there's anyone in Colorado that would like to pick up a healthy 'Sri Kembangan', let me know... It's too big to ship. 

   Kevin

[FlyingFoxFruits]

Don't forget! The small petals of the carambola flower are delicious and tart!  Add them to salads or as a garnish, and if u r really wild and crazy, try it with the fruit of synsepalum dulcificum...it's wacky wild.

[CoPlantNut]

Interesting- I'd never tried eating the flowers before.  The late-afternoon 'Sri Kembangan' flower petals I just sampled were actually fairly sweet, no miracle fruit required.  I'm growing lots of S. dulcificum; I think they are the most "worth the space and effort" of all the tropical fruit trees I've grown so far, in terms of fruit production and "impact" of the fruit.  Miracle fruit are normally required before eating a carambola purchased in a Colorado store, but no star fruit purchased here compares to a good, tree-ripened star fruit!

I wish my carambola trees were being as productive as the miracle fruit.

[lkailburn]

Hi Kevin, There is a nursery here in town: Fort Collins Nursery that actually has some carambola in stock. I think they only have 1 left, it's about 7 feet tall. ...Just incase you wanted a second plant :-)

-Luke

[CoPlantNut]

Hmm...  Haven't been up to Fort Collins to check out the nurseries in many years; looks like I'll have to go up there!

Do you happen to know if their plant is in bloom at the moment?  The last few dozen flowers on my 'Sri Kembangan' have yet to open, but even giving it warm Colorado sunshine and access to real bees for the past 3 weeks still hasn't resulted in any fruit set.  I'd love to try cross-pollinating it with another carambola to see if it is just a self-compatibility issue.

I'm not really looking for a second carambola, just one (good tasting) self-fertile one!

Incidentally, if you'd like another carambola, I'm looking to get rid of at least one of my 'Sri Kembangan' (I have 2).  It may not be self-fertile though... 

   Kevin

[lkailburn]

Sent you a message Kevin :-)


The carambola at the nursery here is Kari, but is not in bloom as far as i remember.

Thanks!

-Luke

[Ethan]

First year I had my SK, it bloomed and set fruit though I did help by brushing pollen from flower to flower.  The plant was too small to mature the fruits and in years since then I cant stop messing w/it at bloom time.  This year it really needed repotting and dropped it's blooms in response though it is flushing heavily now so maybe more blooms in the future?

-Ethan

[WhitH]

For what it's worth, I have a 'Sri Kembangan', the only carambola I have growing. It's been in the ground about 9 months from a 3 gallon, and it flowered a whole bunch a couple months ago, yielding just one fruit, which it held to maturity. Of course, since I am in a neighborhood, it could have been pollinated from someone else's plant. I haven't seen any carambola in the neighborhood, but wouldn't be surprised if there are some relatively nearby. I wish there were a way to peer into everyone's backyard  .

I'll try to report on how well it fruits next time it flowers for me.

[bsbullie]

For what it's worth, I have a 'Sri Kembangan', the only carambola I have growing. It's been in the ground about 9 months from a 3 gallon, and it flowered a whole bunch a couple months ago, yielding just one fruit, which it held to maturity. Of course, since I am in a neighborhood, it could have been pollinated from someone else's plant. I haven't seen any carambola in the neighborhood, but wouldn't be surprised if there are some relatively nearby. I wish there were a way to peer into everyone's backyard  .

I'll try to report on how well it fruits next time it flowers for me.

If you have it planted outside in Veto, you don't have to worry about any trees nearby.  The environment/insects will take care of your pollination.

[HMHausman]

I have several varieties growing together and get loads of fruits so I can't tell you the answer to this from personal expereince.  However, from my memory, I believe they are self fruitful.  Until shown otherwise, that's my final answer.

Harry

[fruitlovers]

I have several varieties growing together and get loads of fruits so I can't tell you the answer to this from personal expereince.  However, from my memory, I believe they are self fruitful.  Until shown otherwise, that's my final answer.

Harry

I thought that too, but look at Morton book. She says that interplanting different starfruit cultivars helps pollination.

[CoPlantNut]

I have several varieties growing together and get loads of fruits so I can't tell you the answer to this from personal expereince.  However, from my memory, I believe they are self fruitful.  Until shown otherwise, that's my final answer.

Harry

Yep, I've fruited seedling carambolas before- and they were quite prolific, so I know they can be self-compatible, but my 'Sri Kembangan' aren't behaving the same way.

   Kevin

[TropicalFruitHunters]

PDF about flowers' short styles VS long style varieties.

http://www.fshs.org/Proceedings/Password%20Protected/1965%20Vol.%2078/375-378%20(KNIGHT).pdf

[CoPlantNut]

PDF about flowers' short styles VS long style varieties.

http://www.fshs.org/Proceedings/Password%20Protected/1965%20Vol.%2078/375-378%20(KNIGHT).pdf

Interesting article.  My favorite quote, especially considering that this article was written in Florida:

"As discussed above, the fact that fruit result from selfing and from crossing similar floral types suggests an incompatibility system which occasionally breaks down. This phenomenon must explain the performance of such clones as the newly named cultivar 'Golden Star' which is reported to fruit well, even when planted in such isolation that the opportunities for cross-pollination must be exceedingly rare."

Isolated somewhere like Colorado or Ohio, I think the opportunities for cross-pollination are an order of magnitude less than anyplace in Florida! 

I have no other carambola flowers to compare with at the moment, but from the description in the article of the anthers being held well above the style, it looks like 'Sri Kembangan' would be considered a short-style type.  The article mentions that they got zero fruit set from short-style X self, and also zero fruit from short-style X short-style.  My experience so far backs this up.

Luke pointed out that a nursery nearby has a 'Kary' in stock (this would be the first carambola I've ever seen at a nursery here in Colorado!); does anyone know if it is a short-style type?  If so, from this article, it wouldn't do me any good to get one even for cross-pollination purposes.

   Kevin

[TropicalFruitHunters]

Maybe they would let you have a couple of nice cuttings from the plant and you could try a few different types of grafts on your plant??

[CoPlantNut]

Maybe they would let you have a couple of nice cuttings from the plant and you could try a few different types of grafts on your plant??

Yes, that would be ideal, although from what the article you posted said, if Kary is a short-style variety, it still may not do me any good.  Worth a try though!

   Kevin

[lkailburn]

Kevin,
I hope to prove you wrong my friend!  Only with the best intentions of course.

So here is the Sri Kembangan that you gave to me a few months. Since I've had it, it has been in continual bloom.
Here is an overal photo of the tree.(with my Lola girl enjoying it's shade  )


Yesterday I counted 22 fruit, though i touched 2 of the smallest(barely visible) and they fell right off so we are down to 20.

But here are the largest of the two.

(this photo you can actually see another fruit out of focus)


I live about 2 miles from a nursery that was carrying Lara, and sri kembangan carambolas. None of the ones they currently have left are in bloom. But they did sell 5 or 6 plants. So it's possible there is another star fruit tree nearer to me..but i doubt we'll ever know.

For both our sakes lets hope this means Sri Kembangan is self-fertile and we can both enjoy some tree ripened fruit by the end of the summer!! 

-Luke

[CoPlantNut]

I'm hoping it really is self-fertile too; the fruit-lets you have have are more than I've ever had before, and I still have another Sri Kembangan the same age and size as yours, just starting another bloom flush now, and I want fruit!

   Kevin

[Guanabanus]

Per my fuzzy recollection, my Sri Kembangan was fruiting just fine before I planted other varieties also.  But I wasn't looking for trouble and didn't take notes.