Cold Hardy Citrus Damage Report #1 ❄️ 16.9°F in zone 7b/8a

[@BackyardBerry]

I love this update. Looking forward to discussing cold hardy citrus in a long form discussion.

[@themulberries]

@@BackyardBerry Thank you! Me too!

[@arthurcaluwaerts3878]

Last year, it got down to 16.5°F. Good windbreaks probably would've saved all the plants if they were dormant. I grow two Owari Satsumas, a Yuzu, and a Thomasville in Belgium with no problems thanks to wind protection. One Satsuma, grafted onto C35 citrange, split its bark on some smaller branches, showing its cold limit. Any colder and it would've been probably fatal. Next year, I'm planting about 20 cold-hardy trees in Belgium that are waiting in the greenhouse. I love your video by the way!!!!! Such a good test ! 🤩

[@themulberries]

@@arthurcaluwaerts3878 Wind protection is so critical! I hope a lot of our trees survive despite the unideal conditions, it will really prove their hardiness. Good luck with your cold hardy trees! Very exciting.

[@rangerismine]

Lots of good data getting recorded here. This will put a lot of those past internet claims on citrus cold hardiness to the test!

[@themulberries]

@@rangerismine Thank you! Definitely, there isn't much nuance to the hardiness data we do have available, and there's so many variables to consider.

[@noahzwiefelhofer]

Great update brother, I enjoyed this. Thank you for sharing

[@themulberries]

@@noahzwiefelhofer Thanks for watching Noah! I appreciate it.

[@XoroksComment]

Great work 👍🏻

[@themulberries]

@@XoroksComment Thank you!

[@mikeadams6538]

Wow....what an amazing study you guys are doing....I am in zone 7a in Southern Pa. I am growing several cold hardy varieties of citrus. I admit I am protecting them with Christmas Lights, styrofoam and plastic. Owari Satsuma, Swingle citrumelo, Taveras LImequat and a Xie Chan. My tree never got below 30 degrees this past week. I love how you guys push your trees to the limit....

[@themulberries]

That's great! Your strategy will yield the highest quality fruit at least. Our goal is to attain as much hardiness as possible, and then select for the best flavor possible. Fingers crossed we attain some decent results!

[@Hydreii]

Great work ! Very interesting results. Here in France (7b) my citrus haven't seen below -4°C (25°F) yet, but I've already had some damage on my small yuzandarin, unfortunately. My sudachi is fine so far, and so are all of my trifoliate hybrids, ichang papeda, yuzus, and hanayus. The real test is gonna be when temperatures dip below -12°C (10°F), but even my yuzus and hanayus were fine last year with these temperatures. I'm slowly trying out more sensitive varieties every year to find out what the limit is for me... But I'd love to be able to grow yuzandarin, clemyuz, changsha, maybe even keraji... I'm planning on crossing some of my potted citrus with a superior selection of ichang papeda, to hopefully create something with similar edibility to clemyuz while benefiting from yuzu-like hardiness. And if I can get my hands on Poncirus+, I'd love to create new citrandarins, citranges and citrumelos as well. I'd love to see how things go for you later this winter, hopefully there's going to be a lot of survivors !

[@themulberries]

@@Hydreii Thank you, I sure hope so! I'm mostly interested in growing the ones that are reliably hardy here anyways, and the rest I can put in the greenhouse. I have Clem-yuz 2-2 inside and outside because I really enjoy it's flavor and sweet-tartness. Yuzu, Ichang Papeda, and their hybrids definitely stand out as being very hardy despite having no trifoliate genetics. I think they still have a lot of potential to create new hybrids, and Poncirus+ would make an excellent parent if it can pass its low resin quality.

[@Hydreii]

@themulberries Yes, I totally agree about their potential. Maybe a trifoliate-yuzu or trifoliate-ichang papeda hybrid could work well to introduce cold resistant genes to citrus while limiting trifoliate influence ? I have a yuzu-citrumelo hybrid that supposedly doesn't have any resin or trifoliate influence in the fruits, and is hardier than yuzu. It has trifoliate leaves though. Hopefully it'll fruit in a year or two so I can verify that. If that's true, then it might be worth trying out similar crosses with a parent that has both trifoliate and ichang papeda genetics.

[@themulberries]

@@Hydreii That's so awesome, I hope that turns out well for you! I'm really eager to see our Tri-clem-yuz and Tri-chang lemon plants fruit in the future. I think they have a lot of potential for both edibility and hardiness.

[@Hydreii]

@themulberries yeah, i hope they'll do well !

[@kathleenebsen2659]

Right-oh! I do have an in ground trifoliate that just laughs at the cold. It fruited this year. The juice wasn’t bad at all.

[@doggiefamily908]

Thank you, that was very informative. I'm bummed about the keraji. I planted mine in the ground this past spring, in the same zone in GA. I'm going to need to protect it some. Thank you for the heads up.

[@themulberries]

@@doggiefamily908 You're welcome! I was hoping this information would be useful. Your Keraji may do better in a sheltered area, otherwise with full sun/wind exposure it performed worse than we expected. Older growth will also stand a better chance at surviving too, since the damaged limbs are younger and thinner.

[@kathleenebsen2659]

Well, you have the 007 test for cold hardiness for the nursery rows. That’s right, Live and Let Die! Folks who are relying on the USDA hardiness zones that have been adjusted for climate warming should remember that it reflects an average. Here in Zone 6, I was adjusted to 7b. A couple of years ago we had the polar vortex dropping our temperatures down to -12*F! Needless to say, I think the new zones are a hefty heap of happy horse manure! I’m planting for the lower zone. Mature trees will resist the cold better than baby ones so I sheltering my young trees until they get a bit bigger. Thanks so much for sharing the results of your trials!

[@themulberries]

Excellent advice, we are also treating our zone like it's previous zone 7b despite it being considered zone 8a. I definitely recommend protecting young plants instead of treating them as brutally as we do 😂 Rule of thumb is hardiness ratings are based on mature, dormant trees.

[@scotte3728]

If it helps here’s a hardiness report from winter 2023. Location: Richmond, VA Low 14, several days with lows in the teens and 20s No 24 hour periods below freezing All were 1 gallon plants planted in the spring. Yuzu, two in ground. Defoliated and some dead wood. Lots of new growth in spring/summer ‘24 but no flowers or fruit. LB8-9 died planted on south side of house Arctic Frost satsuma died - planted on south side of house Ichang no damage. Grew three feet plus summer of ‘24 Bloom sweet grapefruit - defoliated and some wood damage. I cut back the dead wood in spring. Lots of new growth and came back really healthy. Keraji - died Sudachi - died

[@themulberries]

@@scotte3728 This is valuable information, thanks for sharing! Was it Ichang lemon or papeda? Very interesting the bloom sweet did so well. Unfortunately our Keraji will likely suffer the same fate. I'm glad we kept some in the greenhouse! They look much better, haha.

[@scotte3728]

@ yea my greenhouse Keraji, satsuma, and yuzu all produced fruit this year. So much fun picking fruit in December.

[@scotte3728]

Regular Ichang from one green world.

[@themulberries]

@@scotte3728 That's awesome, I agree! We got Yuzu very early this year and they were wonderful.

[@PapaPepper]

Thank you for that

[@CitrusPalmsWithTom]

Thanks for the update! I don’t know if you are amending the soil, but the presence of broom sedge is a reliable indicator of poor fertility.

[@themulberries]

@@CitrusPalmsWithTom Good to know! We amended slightly with compost but nothing serious . This field has pretty poor soil and even worse drainage. It was an old Tobacco farm originally before they began leasing it. I may look to fertilize a bit more next season!

[@joman104]

Crazy how some of them look unfazed

[@themulberries]

@@joman104 I know right? There's a huge difference between even some of the hardiest varieties.

[@quinnM1007]

Awesome report! I think I hit 20F, and my Yuzu looks like yours and similarly my ClemYuz, though I will say it was very interesting to see how some of your Sacaton seedlings reacted differently to the cold and compare them to mine. Do any of yours have that really bright yellow (Trifoliate like) or even a red-ish defoliating color?

[@themulberries]

@@quinnM1007 Thank you! I think I only noticed some bright yellow leaves dropping on our Tai Tri 4N and a few on Tri-clem-yuz #1, but neither have fully defoliated yet.

[@quinnM1007]

Hopefully those will be nice and hardy for you!

[@themulberries]

@@quinnM1007 Thank you! Those two look very promising so far!

[@paul.1337]

My Yuzu graft and grocery store mandarinquat and kumquat seedlings have survived in the Philly suburbs so far.

[@themulberries]

@@paul.1337 That's awesome! Yuzu/kumquat and their hybrids have good hardiness due to their early dormancy.

[@raregrowsNJ]

Interesting that you are getting colder there sooner than here in north NJ! 22f has been the lowest so far, outdoor evergreen hybrids look unbothered. My taitri tree behaves differently than its own rooted cuttings. The main tree has dropped its leaves but the rooted cuttings are still holding all leaves, since they are smaller/shorter the ground must be warmer

[@themulberries]

@@raregrowsNJ I can't believe how cold it's gotten so early in the season! This will really stratify the hardiest of plants. Tai Tri definitely exhibits some variability with leaf drop, and its leaves seem surprisingly resistant to dessication.

[@Sir_Ol]

Hello, I really appreciate your work but I was always wondering I you know whether a seedling is zygotic or not. Can you explain this? By the way greetings from France!

[@themulberries]

@@Sir_Ol Welcome to the channel! Glad to have you here. I can tell when they are zygotic because the leaf shape, color, and sometimes growth habit is different from the mother tree that the fruit came from. Some trees produce very few zygotic seedlings and they can be difficult to distinguish, like with Swingle citrumelo.

[@FahimSheikh-co9cg]

Hey! I am from Bangladesh. I like citrus tree.

[@themulberries]

@@FahimSheikh-co9cg Welcome! You came to the right place! We love citrus trees.

[@realMysta]

So i guess the main test will be for taste?

[@themulberries]

@@realMysta Yes! I've tasted most of the established varieties and have the results posted. Many of them are actually quite good. For our seedlings, I have high hopes for Tri-clem-yuz #1 and OP Sacaton #1.

[@raymondkyruana118]

I was shocked at how cold it's been in NC! Is this unusual?

[@themulberries]

@@raymondkyruana118 It's not unheard of but it does feel unusually early in the year. Last year we saw these temperatures in January!

[@raymondkyruana118]

@@themulberries Dang I always thought it was a warmer climate

[@themulberries]

@@raymondkyruana118 Typically it is, but every 5-10 years it changes its mind!

[@dukeone224]

Do any of these have a history of good fruit production?

[@themulberries]

A lot of them can be very productive! Thomasville, Tai Tri and Yuzu can be particularly heavy bearers from what I've seen. Prague is probably the shyest bearer.

[@jacobblurton3904]

Where are you guys located?

[@themulberries]

@@jacobblurton3904 Central North Carolina, USA.

[@YouADamnWitch]

Michigan State University has a Trifoliate orange in the Beale Garden. East Lansing is 6a previously 5a. Season's too short to get anything more than green fruit.

[@themulberries]

@@YouADamnWitch Interesting, have you tried cutting into the fruit to see if they're almost ripe? An interesting experiment might be testing trifoliate orange strains for earlier ripening fruit in your location.

[@YouADamnWitch]

@themulberries Afaik this is the sole one in the area. I hadn't ripened in October. Mid-Michigan gets a hard freeze by mid October and early snow usually by November. I'm in MD now and flying dragon is common here. I'm collecting seeds for trials on my property in Michigan. I think reduced polyploidy may be an issue for the hard freezes in central MI. -10 for two weeks in January is common.

[@YouADamnWitch]

@themulberries the fruit had immature seeds last time I collected any from Michigan State University.

[@jonathanknobel2014]

I need a pin iris plus so bad, I desire to breed it with a 942x10 degree seedling I have.

[@themulberries]

@@jonathanknobel2014 Keep your eyes peeled this Spring! I'm working on propagating Poncirus+. Your seedling sounds like a good cross!

[@jonathanknobel2014]

@ can’t wait, hard to find anywhere right now.

[@sneakythumbs9900]

"without further ado" *continues to ado for another 2 minutes*

[@themulberries]

@@sneakythumbs9900 This is very accurate.