Author Topic: Report on winter 2017/18  (Read 4019 times)

Zitrusgaertner

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Report on winter 2017/18
« on: April 25, 2018, 06:22:30 PM »
Location Vienna/Austria Zone 7b
After a very mild period of tempertures mostly above 0°C we had one week with minimum down to -15° and daytime temperatures below zero. During this week I protected my Citrumelo 5*, Ichangquat and PTXSunki with thick fleece. C. ichangensis IVIA got only some sunprotection and Chimera "Prague" stayed unprotected. Prague does not show any damage. It is now full of flowers. Citrus ichangensis lost 50% of its leaves but  nu further damage. Citrumelo 5* which is high crafted, has heavy cracks on the bark of the rootstock (PT!) and has lost all its leaves. It will lose wood aswell. Ichangquat is nearly dead, but PTXSunki has no damages. It lost all its leaves as it does nearly every year. I was a little bit frustrated because I thought high crafting would prevent frost-cracks on the bark but t oviously does not. Any ideas why not?

Citradia

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Re: Report on winter 2017/18
« Reply #1 on: April 25, 2018, 08:25:28 PM »
I lost all my hardy citrus that was unprotected except one Dunstan citrumelo and a citradia. We had one week in January that didn't get above freezing. I lost five Dunstan citrumelo, a citradia, Ichang lemons, nansho dai dai, Thomasville citrangquat, and a Morton citrange, and a Rusk citrange. My lowest temp this year was 10 degrees. The trunk on my 10 ft tall Dunstan exploded all around 360 degrees. Dunstans that barely lost leaves that few years unprotected died this winter. They can't handle a week below freezing.

manfromyard

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Re: Report on winter 2017/18
« Reply #2 on: April 25, 2018, 10:17:35 PM »
Despite this past winter not getting as cold as previous ones, I have quite a few deaths. I can only think that the warm winter weather (70s in January), stopped the trees from entering dormancy. When the Nor easterners rolled through, they all got hit. 3 Bloomsweets look dead. Yuzuquat looks dead. 6 year old Citrangequat is green at the base, but the branches were green at first, then died.

It looks like the warmer winters are even more dangerous than the cold ones... >:(

Ilya11

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Re: Report on winter 2017/18
« Reply #3 on: April 26, 2018, 05:31:52 AM »
Very unusual combination of weather conditions this winter. Two verymild periods interrupted by episode of heavy snow with -5C nights and another  week with -9C nights without daytime defrost (20 cm frozen ground)  with strong winds of 85 km/h.

Unprotected plants:
Thomasville- strong damage, most of leaves gone, small twigs are dead.
Citremon Voss- upper  late summer growth is dead, but plant is OK and pushing new growth
Morton- some leaf loss, but will flower soon
5* citrumelo- lost some  leaves on North Eastern side but heavily flowering now
Three meter high Yuzu ( low graft on poncirus)- no damage( it got severe stem cracks last winter)
Ichang Lemon Shangyuan- heavy bark cracks, most probably will die
Ichanquat- no damage
899J-  loss of upper branches, but is pushing a new growth
FDxHamlin (from Roberto) no damage
PTxSunki ( same source) no damage
High  grafted Prague- lost all its leaves, but strongly growing now
ichangensisxsinensis (Tintori via Mikkel)- last summer high stem poncirus graft, lost all leaves, but no twig damage, is growing now
Very big surprise- same age small graft of Slava Michurina (Orange/PT chimera?) undamaged old leaves, actively growing now. I got mother plant from Z.Cernoch in 2010, very  slow development in a pot
Hanayuzu- stem cracks, probably will die
Early St.Ann satsuma seedling -initially no damage, but probably will die because of stem cracks
Taichang seedling ( 2 meters high, no damage in past 6 years) all  small twigs are dead, no growth, probably most of the trunk will be lost
C.ichangensis SRA241- some twig damage, no growth yet
N2tri("Neuezuchtung" PTxichangensis hybrid of B.Voss)  no damage

One layer fleece cover on a surrounded cage frame:
Yubileiny (AsahikanxGrapefruitPernambuko)- dead
Taiwanika- no damage
Bloomsweet ( low stem poncirus graft, budwood from Sylvain- different from Voss plant)- no damage, but not yet growing
Another surprise- "Pseudo Yuko" from Z.Cernoch- plastic cone with open top protection, some twig loss, but one leaf is still green. This plant was desperately dwarf in a pot, I planted it in ground last spring, in November it gave three small yellow fruits  that look and tasted like real lemons.
 
Among my hybrids- lost many seedlings that were perfectly robust during past winters, but still have some  that are not damaged at all.

« Last Edit: April 26, 2018, 05:49:01 AM by Ilya11 »
Best regards,
                       Ilya

Ilya11

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Re: Report on winter 2017/18
« Reply #4 on: April 26, 2018, 05:45:12 AM »
And I forgot to mention the biggest surprise: unprotected Keraji (low poncirus graft, budwood from Tintori plant)-  no damage at all :o
Best regards,
                       Ilya

Florian

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Re: Report on winter 2017/18
« Reply #5 on: April 26, 2018, 12:08:01 PM »
Similar weather here. At first very mild and at the end of February/beginning of March it was very cold with around 10 days below 0C, absolute low was -11C.
Currently, I only have three citrus planted out. My flying dragon is fine, obviously. A Citrange Cunningham 'Livurce' protected by 3 layers of fleece looks dead as a dodo. All the leaves are fried, the branches look dry and the bark split everywhere. And finally, my ichangensis x sinensis only suffered some minor damage on the youngest twigs. It was, however, protected with a little styrofoam house (5cm). I want to give it some time to grow larger and gain hardiness.

maesy

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Re: Report on winter 2017/18
« Reply #6 on: April 27, 2018, 03:41:11 PM »
Dunstan easely can handle 12 degrees. A also had one week non stop below freezing with a max low of 12 degrees. No damage beside maybe 50% leafdrop, wich is normal here.






snek

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Re: Report on winter 2017/18
« Reply #7 on: April 28, 2018, 02:14:58 AM »
Location: Brno / CZ (130 km north of Vienna and about 150 m higher), climate similar as Zitrusgaertner, climate zone 6b / 7.
Temperatures from official measurements.

Very problematic was the second cooling (20.3) after the previous warming (10.3)

Citruses do not grow in loose soil, but in pots.
Some of me Plants are up to 2.4m tall, stems are up to 6cm in diameter.
The plants are winter outdoors in the garden. They are located at the house (U unheated part of the house) in the distance 0-3m. Only in the case of heavy frosts are covered with a car canvas (such as a common plastic with a reinforcement) in two layers.

This way they are grown: Hybrids (Unshiu x P. trifoliata) ITSZ Prague, Morton Nr93, Rusk, Citrumelo SW4475 F2, USA119, Sanford F2 Curafora, Trifeola, Clementina Crete X Rusk, HRS899-A and Mandarin Changsha.

2017/2018 - without any damage
2016/2017 - protection performed at -16.1C. They were slightly damaged some leaves. Only at HRS899-A - all less than 2cm were dead

« Last Edit: April 28, 2018, 02:17:25 AM by snek »

Delvi83

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Re: Report on winter 2017/18
« Reply #8 on: May 20, 2018, 08:45:01 AM »
I observed that poncirus hybrid can lose leaves, without heave damages....for instance, Citran. Thomsaville, can be semi-decidous tree, and even if lose leaves, can bloom and bear fruit the next season...