Author Topic: List of citrus hybrid that would go dormant in winter?  (Read 3013 times)

911311

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List of citrus hybrid that would go dormant in winter?
« on: January 05, 2019, 10:28:42 AM »
    Does anyone have an idea of which variety of citrus or citrus hybrid would go dormant in winter?

    Poncirus trifoliata
    Ichang?
    Marumi Kumquat  (lose leaves at 0F but not sure if considered dormancy)
    Citrangequat?
    Citrandarin?
    Citrumelo?
    Thomasvilles citrangequat?
    Keraji mandarin?
    Sanford curafora?
    Yuzu?
    .......
   

Citradia

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #1 on: January 05, 2019, 10:30:44 PM »
The only citrus that goes dormant in winter is poncirus from what I’ve learned on the forum. Kumquat and their hybrids will go somewhat dormant and are the last to wake up in spring once they have prolonged period of warm weather, which makes them less susceptible to spring freeze damage to new growth. Other than poncirus, all other citrus including poncirus hybrids are very susceptible to prolonged freezing temps that we see in zones 7 and above. Even though my unprotected 15 feet tall dunstan citrumelo with a 6 inch diameter trunk was “dormant “ with most of the leaves off of it, the trunk still split, actually exploded outward, when I had a low of 7 degrees F and it didn’t get above freezing for an entire week last January. My poncirus actually wake up and try to bloom before my hybrids and usually loose their flower buds to freezing weather in spring; however, spring freezes don’t cause die back of branches or split trunks on poncirus like they do on poncirus hybrids.

Millet

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #2 on: January 06, 2019, 02:20:29 PM »
Citrus trees are more susceptible to cold damage during the tree's first 5 years.  A citrus tree will freeze from the top to the bottom and from the outside to the inside.  Flowers are the first tissue to freeze, followed by tender new growth such as leaves and twigs.  Younger tissues will be more affected than older tissues, and smaller diameter wood before larger diameter wood. Young developing fruits will freeze before mature fruits. The smaller the size of the fruit, the faster it will freeze.  Fruits with thin peels will freeze faster than fruits with thick peels.  Freeze damage occurs when ice forms inside the citrus tissue. Some guidelines, though not hard and fast rules to the minimum temperatures that types of citrus trees can survive without damage to leaves and branches are.....Limes 29-F, lemons and grapefruit 26-F, Meyer lemon 22-F, oranges and mandarins 21-F and kumquat 19-F.  Research data indicates trees growing on bare ground have a higher probability of survival than trees growing on turf.  This is because heat from the bare ground radiates stored heat upwards into the tree's canopy.  The difference in the canopy of the tree can be up to 5 degrees warmer. (taken from my notes of Malcolm Manners).
« Last Edit: January 06, 2019, 02:23:49 PM by Millet »

911311

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #3 on: January 06, 2019, 03:27:36 PM »
  Trees that don't go dormant in winter will usually go frozen because of the water inside the tree trunk. I am not sure if it's gonna work if we use dark color water-base paint to cover the tree trunk on winter, as well as using a clear plastic bag to cover the entire canopy on coldest nights and days. As far as I know if we cover the entire canopy by a clear plastic bag, the temperature inside and outside of that bag will be at least 10 degrees in difference provided that the freezing won't last for too many days.

  We can also add a light bulb to ensure, but I think if we plant our citrus trees against the southern or Eastern wall of the house, they will be okay. Someone has tried this method and their lemon tree made it through many winter in zone 6a.

  Oh I forgot about the rootstock. If we use Poncirus Trilofliate we don't have to worry about the root if it was old enough. I think we better use the FD Poncirus to reduce the size of our citrus tree. Don't worry too much about those discourage you not to grow citrus at your zone.  No one has the right to kill your hobby. Go for it. Do experiment and experience it yourself.
« Last Edit: January 06, 2019, 06:33:24 PM by Millet »

Citradia

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #4 on: January 07, 2019, 06:04:19 PM »




I’ve been experimenting. Those are satsumas on flying dragon under plastic with heaters inside.

Sven_chinotto

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #5 on: January 21, 2019, 08:03:19 AM »
When talking about 'dormant', are we talking about the roots that stop working below +- 12°C? In that case, don't all citrus trees go dormant when dropping below that temperature?
Cheerios!

Sven

SoCal2warm

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #6 on: January 21, 2019, 03:55:09 PM »
I don't know what you mean by "dormant", but I have Yuzu and Keraji seedlings planted outside in Olympia, WA (the Pacific Northwest) and as of January 20, they have not lost their leaves.

The leaves are still green and look okay, although have turned a slightly more yellowish green tint since November.

I'm pretty sure the plants have stopped growing though.

Temperatures are constantly cold though almost always above freezing. Although there was some frost in late November.
(The leaves slightly changed their color tint weeks before that)

Also my Dunstan citrumelo still has its leaves and is looking well.
(The leaves on some of the branches you almost can't tell changed at all in color tint)
« Last Edit: January 21, 2019, 04:07:20 PM by SoCal2warm »

Millet

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #7 on: January 21, 2019, 06:55:03 PM »
Citrus growth greatly slows down when the temperature is below 55.4-F (12C),  but  citrus does  not go  completely dormant during the winter.  Unlike deciduous trees that develop their flower buds during the fall months, citrus develop flower buds during the winter months which will then bloom in the spring..

SoCal2warm

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #8 on: January 21, 2019, 07:15:29 PM »
Unlike deciduous trees that develop their flower buds during the fall months, citrus develop flower buds during the winter months which will then bloom in the spring..
Yeah, citrus aren't going to be developing anything in the Winter at 47 degrees latitude.
I see the camellias here beginning to develop flower buds though.

Millet

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #9 on: January 22, 2019, 11:00:23 AM »
SoCal2Warm, in locations that citrus is capable to be cultivated, it is during the winter months that citrus develop the flower buds that will be ready to bloom the following spring.  Is this true for citrus out doors in a Siberian winter .... I'll leave the answer to that question up to you.

SoCal2warm

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #10 on: January 22, 2019, 03:26:28 PM »
SoCal2Warm, in locations that citrus is capable to be cultivated, it is during the winter months that citrus develop the flower buds that will be ready to bloom the following spring.  Is this true for citrus out doors in a Siberian winter .... I'll leave the answer to that question up to you.
I'm sorry, I don't think I understand you.
What about locations where citrus is possible to be cultivated but where it is not possible for flower buds to develop during the Winter?

hardyvermont

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #11 on: January 22, 2019, 03:34:04 PM »
Poncirus grafted onto rootstock in November bloomed before setting out new growth under grow lights.  Could someone share the link about flower initiation on Poncirus and standard citrus?

Ilya11

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #12 on: January 22, 2019, 06:45:53 PM »
Poncirus grafted onto rootstock in November bloomed before setting out new growth under grow lights.  Could someone share the link about flower initiation on Poncirus and standard citrus?

link
Best regards,
                       Ilya

Citradia

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #13 on: January 22, 2019, 07:45:09 PM »
SoCal2warm, I think I can shed some light on Millet’s point about citrus forming flower buds over winter: we learned at one of the south east citrus expos that citrus need some chill hours in winter to bloom in spring, similar to peaches or apples; however, unlike peaches or apples that may need 200 to 400+ chill hours below 45 degrees, a citrus tree only needs a few hours below 45 degrees to bloom. That made me think of the climate of south central FL where I grew up, which is where citrus thrive without care, before greening came around that is. Citrus might be able to survive and grow at a high latitude with winter protection, but that doesn’t mean that citrus is happy or will be fruitful at high latitudes. For those of us in cold winter climates, If we can create a climate for the citrus that resembles their native or natural environment, they will perform better than if we subject them to prolonged cold temperatures. If you’re at such a high latitude that citrus outside stops all growth or goes so dormant that it has no hope of blooming in the spring, it’s probably going to die anyway like it would in Siberia. For example: a satsuma planted outside without protection where I live in western NC might as well be planted outside in Siberia without protection; the tree won’t make flower buds for spring because it’s gonna freeze to death.

Citradia

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #14 on: January 22, 2019, 08:08:55 PM »
SoCal2Warm, sorry for my long previous comments/ explanation. I looked up 47 degrees latitude and that is near Pacific Northwest which is where I think you’re sometimes referencing for citrus trials. It also includes parts of Europe where some of our forum members successfully grow citrus fruits outside. From what I’ve learned, the Pacific Northwest stays cool year round which is not where citrus would thrive naturally in the wild. Citrus like warm weather. If citrus in Oregon survive winter unprotected, they have received enough chill hours to bloom the next spring provided they receive enough heat to grow. Camellias also like to grow and bloom in the south eastern USA and bloom in fall, winter, and spring depending on variety. I can tell you that camellias are more cold hardy than citrus by a whole lot; they grow outside at my house (zone 6b) unprotected and will bloom in fall or spring unless deer or rats eat the plants.

hardyvermont

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #15 on: January 22, 2019, 09:04:23 PM »
Thank you Ilya, that is very helpful

Millet

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Re: List of citrus hybrid that would go dormant in winter?
« Reply #16 on: January 22, 2019, 11:26:11 PM »
hardyvermont,  that is why in my post above I wrote ..."Poncirus varieties excepted" from the rule.