The Tropical Fruit Forum

Very interesting. Did you apply any sun protection? My opinion is, that more citri are killed by sun than by frost alone. They are all on own roots by now, are they? Du you plan to craft some on PT?

That is true, however I lack the space for that, and they're pretty pricey here too, for that price I had a proper glass greenhouse. However I really wished mine was a bit higer, temperature management is difficult at times because the greenhouse's roof height is 2.5m ( = 98.4 inch or so) and it really should be 20% higher at least. But then I'd have to choose a much bigger greenhouse which is wider and longer and again I was not allowed that much space in my garden
I am well aware that the large industrial size greenhouses are heaven in terms of temperature management, even without special equipment to regulate it automatically. But that's something I can only dream of.
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I dream of going professional with my citrus production 

If I'd set up a new greenhouse I would prefer a foilhouse. Modern foil greenhouses offer better isolation than glass houses and you can easily remove the walls.

@Zitrusgaertner Bernhard Voss has an Ichang Papeda at a similiar size of yours. And hardy since years.
Where did you get your plant from?

The seeds came from Bernhard Voss, as far as I can remember. He told me that IVIA would not be very hardy. I kept the young seedlings in the open ground for 3 years. Together with a craftet "very hardy" ichangensis that came from Bernhard. In the first winter the "hardy" C. ichangensis (he tagged it 5*) died and all IVIA seedlings and a few seedlings of another cultivar survived with some damage from winter sun and frost. After three years one or two plants bloomed. I had to repot these plants and some time later planted one of them in ground again and kept another in a container. The latter one bloomed after three or four years. Typival IVIA-fruit. I have a crafted IVIA fom ADAVO aswell. The one from ADAVO had a lot of seeds the fruits of my seedling none.

Quote from: Florian on May 06, 2021, 02:02:20 AM

Funny you should say that. I know several people in Germany and Austria who say that their seedlings are more coldhardy than their plants that are grafted on Poncirus (and also hardier than Poncirus hybrids). I guess it depends on so many factors..

Partially agree with you, my experience with C.ichangensis is very difficult to interpret , its hardiness depends on more factors than that of poncirus. But up to now I have not seen any photos of mature pure ichangensis that survived long term in the Northern part of Europe.

Ilya.
I am really bad at posting pictures but believe me, I have a seedling of Ichangensis IVIA in my garden that now is in ground for round ten years. Is is 150cm high and was never protected and was never damaged from cold. Is is deeply green an looks much healthier than my poncirus which does not like the soil. It seems to be much more resistant to limestone than PT.

I suppose it is possible the tree was originally grown from a seed that came from an Ichang papeda, so genetic recombination, or hybridization is a possibility. It definitely did not have any bad Poncirus trifoliata flavors. And I could even eat the peel, which would be highly unlikely if it was a poncirus hybrid.
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What has Citrus trifoliata to do with Citrus ichangensis? Why should Ichang papeda have Poncirus flavors? But what you have found is no Ichanng papeda. There is a Variety with round fruits and a juicy Pulp, but the fruits of Var. "IVIA" look quite different. Your fruits look like Yuzu as Laaz remarked.

Haydite does not store nutrients therefor it is best for hydro-culture. Broken Haydite might be better. I prefer natural volcano-stuff. It contains several minerals and sulfur.

Thanks Florian for the posting. This hybrid actually seems to be one of the best hybrids selected so far. I will plant this one as well, I am still looking for a source of material (rice or plants). I have a copy of the Poncirus x Changsha seedlings that Bernhard Voss made in the early nineties. The version I have is tested hardy outdoors to -17°C without damage (it was not colder for me yet) and is reliably fruiting every year with fruits, whose skin has 1/3 to 1/4 Poncirin of Poncirus fruits, and the content not at all, pleasant citrus aroma, not sweet, but a bit tangerine-like, for juice, lemonade, jam in my opinion very suitable. I have posted about this several times already. One should take such selected hybrids as crossing partners for further breeding work...then maybe one day you will get a poncirin-free and yet hardy citrus!

Is your 899-Hybrid trifoliate or monofoliate? I have 4 of them. 899A and 899J are monofoliate. 899F an 899H are not. All of them flower.
 

Fruit quality of Poncirus seems to vary a lot from year to year. My fruits of 2019 were quite good (Zdenek said, they were the best he had ever tasted). After two weeks of storing there was quite much juice and very few bitterness in it. We had a very long summer and autumn ended with November or the fist week of December. Maybe the fruits are better when they are riper? We had almost no frost until Christmas and the last fruit of Citrumelo 5* I took home was only as bitter as a normal white grapefruit and had also some sweetness.

Interstock crafting is often recommended as a stragedy to get a seedling to erly blooming. But never tried by myself.

This is my 852 with fruits. Pictures taken last Saturday.

My 852 has serrated leaves that are rather rough. Not that smooth and shiny.

Bernhard Voss update
He does not work in his pottery any more but takes care of a big Citrus Collection and still works as an arborist. His nursery was damaged during a storm and he did not rebuild the tunnel. But you can meet him at the Vienna citrus-fair (Wiener Zitrustage) in Schönbrunn Castle im Vienna.