The Tropical Fruit Forum

Very nice work! I am thinking about something like this since a long time. Congrats!
Here are some ideas I would like to contribute for everyone how is interested:

In Germany there is a company using a greenhouse around the house to heat it. The oven is placed outside in the greenhouse cause it is too warm otherwise. To prevent mold it is vented on top and walls are water vapour permeable. Water vapour will follow natural vapour pressure from inside to outside. No mold and rotting issues. Radon is discharged to the outside.
These houses have very low heating costs. But your area is definately colder in winter but might have more sun in winter?
https://www.bio-solar-haus.de/

This might be the same house in Sweden like in the link from lebmung
https://lantliv.com/lantliga-hem/vi-byggde-vart-hus-i-ett-glasvaxthus/

There is a very clever way to heat a greenhouse (and the house) in Nebraska made by Russ Finch.
This won`t work in Germany cause soil temperatures are colder due to missing snow cover in winter.

https://www.youtube.com/watch?v=ZD_3_gsgsnk

http://www.citrusinthesnow.com/

Is there a more detailed description of your house somewhere? I am interested in technical details like floor plans, ventilation,  air flow etc.
Would be really interesting!

What is the rootstock?

I cannot tell. Poncirus or Citrumelo I guess.

yes

roots seem to be fine. no dead ones.

This is a supposed US852. All new growth is yellowish and is barely growing. What is it?

A few weeks ago I repotted it and fertilized it. No reaction.
I haven't found any pests except a few brown spots.

Do you bend the top to induce it to bloom?

The trifoliata that falls from my tree sprouts in clumps where the fruit fell in the fall, nothing will touch it. We have coons, possums & armadillos around & they never touch the poncirus.

This might be the advantage of Poncirus tastes.... when seen from the Poncirus point of view.

yesterday I saw a fruiting Eriobotrya at the cologne zoo. This winter was very warm (I have no idea how cold it was in Cologne) The specimen at Botanical Garden in Bonn is not the only one in that region this year.

Recently I received seeds of N1tri from Ilya. Here are some seedlings
N1tri F2 by michaelbasso, on Flickr
N1tri F2 c by michaelbasso, on FlickrN1tri F2 b by michaelbasso, on Flickr

leaves are different from palnt to plant, mostly monofoliate but some are more or less trifoliate. Some are bi or trilobed like e.g. Passiflora leaves.

 a genetic population with 220 hybrids between F. hindsii and F. crassfolia has been successfully bred and cultivated on a just 10 m2 horticultural shelf. Based on this population, a fine genetic map for fruit-related traits has been under construction in our lab. In addition, a juvenile period of eight months of F. hindsii is the shortest among the early flowering germplasms in the citrus taxa to our knowledge (Tong et al., 2009), suggesting the prospects of generating BC1, F2 or even introgression lines based on F. hindsii. More importantly, all previous transgenic F. hindsii lines carrying different sequences blossomed and bore fruits in their first or second year (Cao et al., 2015; Liu et al., 2017c; Zhang et al., 2009), suggesting that genetic modification does not disturb its intrinsic feature of short juvenility.

interesting. hindsii plants are easier accessable and crossings are easier reproducable than those with C.wakonai. But in case of of early flowering it might be still topped by C.wakonai. But in opposite to it hybrids still keep precocious flowering trait. As far as I know C.wakonai hybrids loose this trait in further generations.

Found the link: This is the plant from Horst. The same as Sylvains.

http://yuccaundanderefreilandsukkulenten.xobor.de/t1071f9-Erstbluete.html

@usirius okay. This encourages me to give it another try.
Do you have any picture of the two types you spoke of?
I know of a plant in a botanic garden in Germany and another one in a private collection which is already flowering. But I haven`t heared of fruits so far. No idea if these are the same plant.