Roberto,

This winter has been terrible in the Paris region, my garden got -16C one night with almost 7 weeks of daytime negative temperatures and a lot of snow.
This kind of winters occurs here once in 30 years.

Nevertheless, up to now most of my citruses are OK. I was not protecting my plants with the exception of citremon ( garden fleece for one week) that lost eventually upper part of the trunk and got a nasty frostbite close to the ground. It is pushing a new growth:


but I am still struggling with its wilting due to numerous frostbites and spread of fungal infection.

Almost no damage to Swingle F2 that even starts to flower:


I got also no damage to Citrumelo Batumi, but at the end of winter we had a terrible storm of more than 130 km/hour that almost uprooted this citrumelo and I was obliged to cut it to the ground. It is starting to push new growth.

Ishangquat has not been much damaged by the winter ( only few upper twigs were frozen), but was badly bended by the storm. It is pushing a new growth now:



Citsuma Prague lost most of the leafs but is pushing a new wigorous growth:


HRS899"J" was damaged much more, with some frozen terminal twigs, but is starting to push a new growth.

Thomasville lost the upper third of the trunk, but is starting to flower on one lower branch:


Morton lost all the leafs but is flowering now:

Hi Ilya,

Congratulations, you are lucky. Bernhard Voss from Hamburg, whom ''I met last weekend in Vienna, has lost lot of his plants. One of them Ichangquat. Your plants seem to have a lot of protection from walls around.
Greetings from Vienna
Robert

Roberto,
I agree, walls are playing some role, but not when the frost persists for a long period. Actually in the strong winds they could be a damaging factor due to "chimney" effect.
We had an exceptionally mild weather last 10 years and my citruses managed to become large mature trees. But of course, if winters like the last one will continue they all will die.

Ilya,

I think beneath heat radiation the benefit of walls is sun protection. Again I had to recognize that sun is the most damaging factor after a long freeze period. At the end of the great frost some of the plants looked quite well but then sun came out an hurt them seriously. Maybe if I had put a box over them there would be less damage.

You said you had to cut down your Citrumelo -have you gut any budwood left?
Salut
Robert

Roberto,
I cut this citrumelo near the ground, it is now starts pushing new growth close to the budding point. So I hope it will recover.