Citrus tolerant of 0 degrees

[Audi_o_phile]

@vnomonee

Link is broken

Here ya go!

Citrus in Zone 5

We don’t think of anyone ever being able to grow oranges or any type of citrus in zone 5. The idea seems ridiculous but its not as bad as it seems. Some people grow a small citrus plant in zone 6 called a trifoliate orange http://edis.ifas.ufl.edu/m/#publication?id=HS221. I’m not going to say its perfect fruit as they are the size of golf balls and packed full of seeds. The fruit is closer to lemon they say than orange. I have grown a couple of plants from seeds outside in zone 5b/6 for the…

[vnomonee]

Thanks for the link, so after reading a bit of that study and specifially what they tested, the Chongyi wild mandarin can be hardier than Poncirus under specific circumstances. Prolonged chilling stress and membrane stability being one of the differences during exposure to 0°C (32°F) not 0f. It performs better than Poncirus but the study did not prove that it can survive lower freezing temperatures than Poncirus since they didn’t test the absolute lows (remember that Poncirus can survive way below -18c/0f) That being said those characteristics in the mandarin would be useful in breeding into Poncirus and other citrus. I am thinking especially for places that can experience abrupt/late freezing. I had lots of bark damage on my Poncirus trees after a late freeze of 27f in the spring. Had basically a complete girdle on one of the trees from the bark splitting in the middle of the trunk.

[Fusion_power]

@vnomonee

those characteristics in the mandarin would be useful in breeding into Poncirus and other citrus.

This is exactly the conclusion I reached. It is potentially valuable breeding material but not for the reason of being more cold tolerant than Poncirus. It has very high potential to enhance some of the traits Poncirus already has, such as making it more tolerant of rapid changes in temperature, especially near freezing (0C or 32F).

[KS_razerback]

If you’ve seen some of the videos of the damage results that @themulberries has on his various hardy hybrids some specific seedlings had tender undignified growth that was unaffected by temperatures to the teens (I think it was). My trifoliate seedlings any tender growth was frozen off as soon as it frosted.

[a_Vivaldi]

And it’s worth pointing out that the study was comparing an evergreen species with a deciduous species, and only the leaves, and only at 32 F. Frankly, I see no benefit in a study that shows that a deciduous species has deciduous leaves.

If they compared this wild mandarin against satsumas or Changsha, and tested 32 F, 15 F, 10 F, and 5 F, and tested the leaves and the bark, then I’d be interested in what they found.

In my opinion it’s a junk study.

[vnomonee]

actually thanks for pointing that out, the fact that poncirus is deciduous totally went over my head lol and this is from someone growing a bunch and its hybrids