Tropical Fruit Forum - International Tropical Fruit Growers

Citrus => Cold Hardy Citrus => Topic started by: SoCal2warm on March 24, 2018, 09:11:54 PM

Title: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on March 24, 2018, 09:11:54 PM
I've observed that citrus grown from seed seems to do better, showing apparently more cold hardiness and being able to survive compared to the grafted plant that died.
I've observed this with lemons and kumquats, and there's also the white grapefruit growing at the Chelsea Physic garden in London up against a protected corner which was originally raised from seed before being planted outside after many years.

This is an interesting observation because the vast majority of the time, when people attempt to plant citrus outside to see if it can survive where they're at, the citrus came from a nursery and is on grafted rootstock.

These observations are coming from zone 8, in the Pacific Northwest. I have no doubt these plants would do much better on Flying Dragon rootstock in colder climates. But here they seem to grow more vigorous and be less susceptible to losing leaves on their own roots. I've also had a few plants on Flying Dragon or citrange that had most of their stems turn brown and die back whereas the seed-grown ones were more resilient. My Satsuma mandarin on unknown rootstock (it's dwarf though) also has not done as well as another Satsuma grown from seed, despite the seedling starting out smaller.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Zitrusgaertner on March 25, 2018, 02:16:24 PM
in some cases I have made the same observations: crafted C. ichangensis (marked as very hard, crafted on PT) died in its first winter surrounded by C. ichangensis IVIA seedlings that survived. And this winter a PT crafted on PT died because of frost-cracked bark. I need not say that all PT on their roots (even the ones in pots) survived. On the other hand I did not have any problems with scions high crafted on PT. The ones that died were young crafts or crafts just above ground.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Radoslav on March 26, 2018, 09:20:00 AM
It is not a question of cold hardiness. There is never a full simbiose between graft and rootstock, rootstock see graft as alien, tries to over grow it.
And in stress situation like drought, frost etc. grafted part is usually the one, who suffers the most.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on August 12, 2018, 10:54:31 PM
North Waco family's orange tree a miracle on 15th Street
by J.B. Smith, January 2013

A tree that Juana Delgado grew from the seed of a grocery store orange has become a miracle on 15th Street.

This month, Delgadoís family has harvested an estimated 600 oranges from the tree she planted 15 years ago when she moved into the Habitat for Humanity home near North 15th Street and Colcord Avenue.

In recent weeks, the family made big jugs of orange juice, shared fruit with passing vagrants and sent their children door-to-door to give away large bags of juicy oranges.

The tree has defied the conventional wisdom that oranges can't survive the Central Texas winter, when temperatures usually dip into the low 20s.
But the tree has soldiered on, even through a January 2010 cold snap when temperatures plummeted to 8 degrees.

"Many people said itís not possible," Delgado said in Spanish. "I say, 'Come look. It's possible.'"
Mark Barnett, a McLennan County master gardener and a landscaper by trade, said he has seen many people try to grow citrus trees they bought from big box stores, but the trees usually freeze and die.

"It's very unusual for it to have survived that long without protection," he said. "We've had some extremely cold winters that should have killed it."
Delgado started the orange tree in a pot using a seed from an orange she bought at an H-E-B supermarket. Most table oranges are improved hybrid varieties and tend not to reproduce faithfully by seed, Barnett said.

But Delgado's oranges turned out sweet and flavorful. Delgado has been harvesting a few oranges a year during the last decade but got her first big harvest two winters ago: A basket and a box full. In the 2011 drought, she kept the tree alive by watering it but ended up with only three oranges that season.
This year, she hit the jackpot. Her children and grandchildren climbed ladders to pick the fruit and filled six boxes with about 100 oranges each.

https://www.wacotrib.com/news/north-waco-family-s-orange-tree-a-miracle-on-th/article_3928e5be-b811-52ef-8dee-465b5788e6ae.html (https://www.wacotrib.com/news/north-waco-family-s-orange-tree-a-miracle-on-th/article_3928e5be-b811-52ef-8dee-465b5788e6ae.html)


Waco, Texas, is in zone 8a, and is just a little south of Dallas.

Although in recent years the 8b zone has been moving north, first the southern half of Waco was reclassified into zone 8b, and now on the latest maps zone 8b has engulfed the entire city.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Millet on August 13, 2018, 12:51:59 AM
Nice things happen to those who wait.  Great story. Thanks SC2W for thinking of us.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Zitrusgaertner on August 13, 2018, 01:58:12 PM
Reminds me of Juanita tangarine. The originial plant is said to have survived -18įC (?) but graftet Juanita's resistance to frost is far from that.

Title: Re: citrus grown from seed shows more cold hardiness
Post by: mikkel on August 13, 2018, 02:17:18 PM

https://www.wacotrib.com/news/north-waco-family-s-orange-tree-a-miracle-on-th/article_3928e5be-b811-52ef-8dee-465b5788e6ae.html (https://www.wacotrib.com/news/north-waco-family-s-orange-tree-a-miracle-on-th/article_3928e5be-b811-52ef-8dee-465b5788e6ae.html)

We recognize you are attempting to access this website from a country belonging to the European Economic Area (EEA) including the EU which enforces the General Data Protection Regulation (GDPR) and therefore access cannot be granted at this time. For any issues, contact wemmons@wacotrib.com or call 254-757-5757 or 800-678-8742.

Someone can help?
Title: Re: citrus grown from seed shows more cold hardiness
Post by: mikkel on August 13, 2018, 02:18:39 PM
solved.
Found it in Google Cache.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Millet on August 13, 2018, 09:59:24 PM
I once ask Dr. Malcolm Manners if citrus trees started from seed were more cold hardy that grafted trees.   Dr. Manners said no.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Zitrusgaertner on August 14, 2018, 03:13:39 PM
Dr Manner's estimation or result of scientific investigation?
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Millet on August 14, 2018, 09:52:16 PM
Zitrusgaertner,  I can see you do not know of Dr. Malcolm Manners, or you would have never asked that question.  Dr.Manners  holds the Chair of Citrus Studies at Florida Southern Collage. He is one of the best known minds concerning citrus in the USA.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on August 14, 2018, 10:28:11 PM
Sometimes what is regarded as common knowledge can be wrong though. Sometimes a specific experiment to answer that question has never been carried out, or only applies to specific situations (certain varieties, a certain climate zone).
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Ilya11 on August 15, 2018, 03:51:04 AM
What I learned from my 25 years of experience of growing hardy citruses in a open ground- is to never generalize. I am sure that Dr. Manners will agree with me ;)
Different root/bud combinations are showing drastically variable responses to winter conditions. A seedling grown in situ with deep principal root has certainly an advantage over a plant grafted in a pot on a stock with shallow roots.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: lebmung on September 07, 2018, 02:58:59 AM
Gene plants express adaptability. What is happening over the years to a plants it incorporates is the DNA.  Natural mutations occurs so the plant can survive. Plants can't run for shelter like animals so they have only one choice adapt or die.
From my experience with kaffier lime, those that I grow from seeds show a large variety. Some do well and others don't.
The seedling grown in cold weather don't die as compared to trees grafted with a scion from Asia.
Also the grafts with the scion from the seedling don't die.
In my opinion it's not about the graft union so much, as to the adaptability of the plant.
A seedling exposed to cold weather over the years will express genes of cold resistance that will pass to the next generation. Of course this happens over the years.  Perhaps hundreds of years.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on September 07, 2018, 01:32:59 PM
A seedling exposed to cold weather over the years will express genes of cold resistance that will pass to the next generation. Of course this happens over the years.  Perhaps hundreds of years.
That's not really true (or possibly I am just misunderstanding your statement, if it was a poor translation). The theory of inheritance of acquired characteristics (Lamarckism) has been largely disproven since the theory of Evolution and by modern genetic understanding.

Sometimes a seedling will exhibit more cold hardiness than its parents. That's what can sometimes happen when the genes get mixed around.
This would be a zygotic seedling, of course, since nucellar seeds have the same exact genetic composition as the fruit parent, except in rare cases of seed/pollen mutations.

One well-known example that comes to mind is Juanita tangerine, grown from seed which came from an ordinary supermarket-bought mandarin.

Over a long timespan, if a species is continually propagated from seed over several successive generations, there can be some level of adaptation if the progeny that are better adapted have a higher rate of survival or reproductive propagation.

So genetics is another factor that can sometimes cause seed-grown offspring to be a little bit cold-hardier than their parents.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: shah8 on September 08, 2018, 04:01:30 AM
Lamarkism, to a limited degree, and on the smaller scale, is a definite valid theoretical foundation for inheritance.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on September 09, 2018, 03:38:22 AM
Lamarkism, to a limited degree, and on the smaller scale, is a definite valid theoretical foundation for inheritance.
To an extremely limited extent, and it's not entirely clear whether that is the case with citrus, so that is really beside the point.

(Of course science has validated a little bit of truth to Lamarkism, like activation or deactivation of certain genes, and methylation of DNA bases, but I did not want to mention that and overcomplicate things, I think it's pretty doubtful citrus is going to be able to pass down its cold-hardiness gene expression adaptations to its nucellar seed)
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on September 10, 2018, 02:50:22 PM
Lemon tree grown from seed survives left outside in a large container over the Winter in Tennessee
http://growingthehomegarden.com/2010/07/lemon-tree-in-tennessee.html (http://growingthehomegarden.com/2010/07/lemon-tree-in-tennessee.html)

He grew the lemon for 13 years before leaving it out outside on his porch. He says he is in zone 6b.
 There's a picture of the tree, it looks healthy and about 3 or 4 feet tall.

He also says in a later comment that his porch is on the North side of his house, and gets no sun in the Winter.

"Every winter the last three years we've seen a -10 temperature appear on the thermometer multiple times. The measurements were actually taken near the house which may be a little warmer than farther out in the yard. We definitely get cold here!"
(that would be degrees Fahrenheit)

Another anonymous commenter also left this comment: "I have a Lemon tree that has lived outside for 3 years with Lemons on it now. I live in Tn." (Tennessee)


Title: Re: citrus grown from seed shows more cold hardiness
Post by: Ilya11 on September 11, 2018, 08:40:00 AM
Lamarkism, to a limited degree, and on the smaller scale, is a definite valid theoretical foundation for inheritance.
To an extremely limited extent, and it's not entirely clear whether that is the case with citrus, so that is really beside the point.

(Of course science has validated a little bit of truth to Lamarkism, like activation or deactivation of certain genes, and methylation of DNA bases, but I did not want to mention that and overcomplicate things, I think it's pretty doubtful citrus is going to be able to pass down its cold-hardiness gene expression adaptations to its nucellar seed)

Very superficial statement. In plants both somatoclonal variation ( due to mutations arising and darwinistically selected in individual cells of multicellular organism) as well as environmentally induced epigenetic modifications can be transmitted to  to clones or  maintained in zygotic seedlings.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on September 11, 2018, 11:58:41 AM
In plants both somatoclonal variation ( due to mutations arising and darwinistically selected in individual cells of multicellular organism) as well as environmentally induced epigenetic modifications can be transmitted to  to clones or  maintained in zygotic seedlings.
That's very fascinating but I haven't seen much evidence of this (epigenetic modifications passed to clones or seedlings.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Ilya11 on September 11, 2018, 12:57:14 PM
That's very fascinating but I haven't seen much evidence of this (epigenetic modifications passed to clones or seedlings.
(https://a.radikal.ru/a24/1809/87/c4e2e63f97e6.jpg) (https://radikal.ru)
Title: Re: citrus grown from seed shows more cold hardiness
Post by: lebmung on September 17, 2018, 05:04:29 PM
A seedling exposed to cold weather over the years will express genes of cold resistance that will pass to the next generation. Of course this happens over the years.  Perhaps hundreds of years.
That's not really true (or possibly I am just misunderstanding your statement, if it was a poor translation). The theory of inheritance of acquired characteristics (Lamarckism) has been largely disproven since the theory of Evolution and by modern genetic understanding.

Better said a seedling exposed to cold starts to acclimatize with time, those traits will be passed down to the next generation. Adaptability: plants can't run when cold comes like animals do.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on December 30, 2018, 07:43:52 PM
I found this post archived on the old Citrus Growers forum:
____________________________________
Skeeter
moderator
Location: Pensacola, Florida zone 9
9 March, 2010

I have been surprised at the cold tolerance of my sister's Owari satsumas--on their own roots. They survived mid teens with no protection and little damage--for several nights. There are not a lot of citrus that taste better either.
____________________________________
Title: Re: citrus grown from seed shows more cold hardiness
Post by: lavender87 on December 30, 2018, 08:36:36 PM
 Most of trifoliate orange rootstocks used were created from cuttings and of course they were much weaker than trifoliate orange roostocks which were grown from seeds. That might explained pretty well why even grafted citrus trees on trifoliate rootstocks from nursery were usually less cold hardy than the one grown from their own seeds.

  Trifoliate orange is a very slow-grow species, so it is much quicker to multiply by cutting branches from a matured tree than germinating seeds; and that is why people rarely used trifoliate rootstocks from seeds. In normal condition, it would take at least 3 years before a seed-grown trifoliate seedling to qualify as a rootstock, but it only take 8 months to a year to get a ready-to-graft rootstock if we use a cutting from a matured trifoliate orange tree.

  Moreoever, the grafted part often requires at least 2 to 3 years to fully unify with the rootstock it was parasitized on. Most of growers have made the same mistake when they were too hurry in testing out their grafted citrus outside when the grafted part and the rooststocks did not actually unifiy yet, and soon claimed that their citrus from seeds are more cold hardy than the grafted citrus on trifoliate rootstocks.

  Don't use naked eyes to hastily judge the grafting joint. It might look pretty good as if it was 100% succesfully unified, but in fact the rootstock and the grafted part were still adjusting over time and would take years to really accept each other as their own.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Millet on December 30, 2018, 09:26:12 PM
This subject came up on the old forum, and I remember at that time Malcolm Manners writing that he thought seedlings were no more cold hardy than grafted trees. 
Title: Re: citrus grown from seed shows more cold hardiness
Post by: lavender87 on December 30, 2018, 10:37:00 PM
Better said a seedling exposed to cold starts to acclimatize with time, those traits will be passed down to the next generation. Adaptability: plants can't run when cold comes like animals do.

  I agreed. Plants did pass down cold resistent gene to the next generation, but the natural mutation happened randomly in a few seeds of some fruits and unfortunately most of the seeds landed in the trash can or seedling die under heavily shaded area.

  In the wild, when weather zone shift suddently, plants will try their best to adapt to the new environment as well as wake up some silent gene to pass down to the next generation; however, most of the seedlings (offsprings) will die, and only a few seedlings with a more adaptable gene will survive to the new environment.

  It is nearly impossible to tell which fruits contain the evolved seeds. I wish we could select those evolved seeds to improve the line then it would be much quicker to create a type of tree with delicious fruits and much more cold hardy.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on December 30, 2018, 10:40:53 PM
I'm not very confident even the rare seedling will show much more cold hardiness than its parents.

(Unless that seedling originated from a heterogenous hybrid involving cold hardy hardy cultivars)
Title: Re: citrus grown from seed shows more cold hardiness
Post by: lavender87 on December 30, 2018, 10:50:42 PM
I'm not very confident even the rare seedling will show much more cold hardiness than its parents.

(Unless that seedling originated from a heterogenous hybrid involving cold hardy hardy cultivars)

   As I said, we were impossible to select the correct evolved seeds because not all the seeds from a crop would have equal chance to germinate and to prove itself as a worthy one.

   Hybridizing is the only reliable way to improve the quality at this time; however, even inside those fruits from hybrid trees there were self mutated seeds with the quality we wanted, but those rare evolved seeds again might have landed in our trash can.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Ilya11 on December 31, 2018, 12:05:50 PM
Most of trifoliate orange rootstocks used were created from cuttings and of course they were much weaker than trifoliate orange roostocks which were grown from seeds. That might explained pretty well why even grafted citrus trees on trifoliate rootstocks from nursery were usually less cold hardy than the one grown from their own seeds.

  Trifoliate orange is a very slow-grow species, so it is much quicker to multiply by cutting branches from a matured tree than germinating seeds; and that is why people rarely used trifoliate rootstocks from seeds.
Are you sure that this a case for poncirus trifoliata, not for its hybrids like citranges and especially for citrandarins?
Poncirus is rather difficult to root, at least in Europe it is mostly propagated by seeds. Its seedlings are rather vigorous, in my climate one season is enough to reach a size for grafting, with the exception of Flying Dragon that is slow and requires 2 to three years.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Millet on December 31, 2018, 01:03:07 PM
One of the criteria for the acceptance of a rootstock cultivar is the amount of seed the fruit provides.  Almost all commercial root stocks are produced as seedlings and not a rooted plants.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Ilya11 on December 31, 2018, 01:19:20 PM
Millet,
Many valuable citrandarin rootstocks like US852 or Forner-Alcaide 5 are giving too many offtype zygotic seedlings and preferentially are multiplied by tissue culture or rooted cuttings.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Millet on December 31, 2018, 01:30:26 PM
Ilya11, I realize that there is exceptions to the rule.  There are exceptions to every rule.  However, most rootstocks are grown from seed.   One of the disqualifications to whether a rootstock is accepted as a commercial variety is the amount of zygotic seedlings are produced. Citrandrin only produces a small percentage of nucellar plants.  Therefore it was discontinued as a root stock variety. As you wrote concerning Flying dragon, it is a very difficult root stock to root.   In the current days of HLB some new acceptance rules are, or will be considered I'm sure.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: lavender87 on December 31, 2018, 02:47:46 PM
Surprisingly, flying dragon branches can root if we collect cuttings at the right time of the year, by simply dipping them in a cup of water for 2-3 weeks. I did not try this method myself, but somebody tried and had great success.

  It is not hard to check whether a rootstock is from seeds or from cuttings. By checking the root of the grafted plant, try looking for the tap-root, if no taproot presents, in most cases the rootstock was from a cutting.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Zitrusgaertner on December 31, 2018, 04:21:06 PM
Some PT-seedlings have taproots, others don't.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Millet on December 31, 2018, 05:10:02 PM
Zitrusgardner, is this true?  Which PT seedlings do not develop tap roots?  Long taproots is the normal  characteristic of seedlings.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Ilya11 on December 31, 2018, 06:20:25 PM
  It is not hard to check whether a rootstock is from seeds or from cuttings. By checking the root of the grafted plant, try looking for the tap-root, if no taproot presents, in most cases the rootstock was from a cutting.
Again not true, a tap root is often cut when seedling is transferred from ground to the pot, it is not providing particular advantage for the potted plants.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Radoslav on January 01, 2019, 02:32:00 AM
This discussion about pros and cons of trifoliata seedlings and rooted cuttings is quite hypothetical.
First of all as Ilya wrote, it is practically impossible to root wooden trifoliata cutting. I remember, that someone posted scientific work about it at old forum.
Secondly, I do not know a single nursery which produce trees for field use in citrus producing countries, which use poncirus trifoliata as rootstock.
Thirdly such nurseries, do not propagate so called "hardy cultivars" for zone 7.

As far as I know, only nurseries for hobby growers like Adavo use poncirus trifolita as rootstock for some "hardy" cultivars, (their standard rootstock for the most cultivars is rooted citrumelo cutting I think).

And I do not believe that rooted cutting is weaker than seedling. For citruses, which root well, like pummelos, the root ball is really strong and dense in the case of rooted cutting.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on January 01, 2019, 02:43:34 PM
And I do not believe that rooted cutting is weaker than seedling.
I'm not inclined to believe that either. (although who really knows?)
My purpose to starting this thread was not to say that there is a difference between grown from seed and rooted cuttings,
I was simply speculating on the effects of being grafted onto different rootstock. That's the discussion I was trying to focus on.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Millet on January 01, 2019, 03:08:08 PM
Radoslav, the Flying Dragon Nursery of Jacksonville, Florida  is another nursery that  uses flying dragon as their rootstock
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Darkman on January 11, 2019, 12:51:18 AM
Whether it does or not must be prefaced by the seasons highs and lows. I had a 15 year old seedling grapefruit tree. never had any cold issues till 2014. this tree was huge with a 14' base and nearly twenty foot tall. lows of 18 started its demise with defoliation and tip damage. borers killed it the following year.

My point is that it wasn't the 18 degrees, it was the lack of cold temperatures leading up to the 18. Lack of suitable temps to harden off the tree was the biggest problem. I will say that the tree would not of died if the borers had not attacked. They probably would not have attacked if not for the tip damage. In 2014 I  lost nine other trees to the freeze. No borers were involved in their death.





Title: Re: citrus grown from seed shows more cold hardiness
Post by: Millet on January 11, 2019, 03:05:15 PM
Charles nice seeing you posting again.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on January 13, 2020, 07:54:12 PM
I will be conducting a specific test over this winter.
The below picture shows two Ichang papeda plants, one on trifoliate rootstock, the other rooted from a cutting on its own roots. The one on rootstock (to the left) might just have yellowish leaves because it had been growing in a greenhouse and was brought outside in September. I've found that hardy citruses (of all different types) don't handle rapid temperature changes very well from growing inside a warm area to being placed in the colder temperatures outside (even if it's not extremely cold).
(https://i.postimg.cc/svqY3hHg/20200113-163354.jpg) (https://postimg.cc/svqY3hHg)

This side by side experiment should be interesting, because I specifically wanted to look at ichangensis and related hardy citrus to ichangensis, and specifically wanted to look at this behavior in zone 8.
Soon we should have a more sure answer whether ichangensis grows better on rootstock or not, when surviving cold climate conditions.

Of course since this is in the PNW climate, cold snaps shouldn't make any difference (the temperatures are pretty steady, it's not going to get warm enough for the plants to come out of dormancy) and things are so wet & damp there's no worry of cold wind causing anything to dry out.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Florian on January 14, 2020, 03:49:11 AM
Is it the same ichangensis clone? They can vary quite a bit in coldhardiness.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on January 14, 2020, 03:10:58 PM
Is it the same ichangensis clone? They can vary quite a bit in coldhardiness.
I don't know. They came from two different sources.
But I would still imagine they are probably the same, because ichangensis is pretty rare around here, and people usually do not grow them from seed. (Especially in this short season region, and all the more so because when was the last time you found seeds in an ichangensis fruit?)

(Both came from Portland, but from separate places)
Title: Re: citrus grown from seed shows more cold hardiness
Post by: poncirsguy on March 18, 2020, 09:15:23 PM
I am going to plant my seed grown meiwa kumquat tree in a raised hard pan clay hill so that it will grow in a slow cold hardy compact form to see how it handles cold weather.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: hardyvermont on March 18, 2020, 09:54:06 PM
I am going to plant my seed grown meiwa kumquat tree in a raised hard pan clay hill so that it will grow in a slow cold hardy compact form to see how it handles cold weather.
Try high grafting Meiwa at 4 ft onto poncirus and let some of the poncirus side shoots grow.  Multiple very high graphs of 50% poncirus  hybrids survived without damage 6 degrees F several years ago.  My bought Meiwa is only now ripening fruit and  Marumi was ripe last month, so it may not be ideal unless they can be persuaded to bloom earlier. 
Title: Re: citrus grown from seed shows more cold hardiness
Post by: poncirsguy on March 19, 2020, 11:42:34 AM
I am zone 6a=-10F so a 4 foot high PT graft will not be an option for me.  I can't protect anything that high up on PT and the tree above the graft.  I have thought about sinking my tree in a 3 foot deep well for a high graft to work.  I can't graft and would have to pay someone to do that for me.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Citradia on March 27, 2020, 09:22:59 PM

(https://i.postimg.cc/DWVKzLCS/BA1-F2958-F99-F-4-E6-F-BBB2-0-D7435772-A52.jpg) (https://postimg.cc/DWVKzLCS)

(https://i.postimg.cc/hJGt99Lp/EF9-AEDBB-A03-C-457-F-BAB8-7-EBC3-C5-D8198.jpg) (https://postimg.cc/hJGt99Lp)
Hereís my meiwa grafted on flying dragon. I have great fruit now, but it has to be covered and often heated with small space heater in winter here from end of October to sometime in April usually to keep fruit from freezing and to keep tree alive since kumquat not hardy unprotected for extended period of time in single digits Fahrenheit. Of course I vent it when temps get above freezing and especially if gets into 50ís.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Millet on March 27, 2020, 10:28:23 PM
Citradia, at what altitude are you located?
Title: Re: citrus grown from seed shows more cold hardiness
Post by: poncirsguy on March 27, 2020, 11:01:48 PM
Citradia  Very nice looking Meiwa.  gives me a little hope on my 5 Meiwa trees.  My seed grown fukushu has its own winter enclosure
(https://i.postimg.cc/d7fyBRqq/IMG-0146.jpg) (https://postimg.cc/d7fyBRqq)
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on April 02, 2020, 12:17:15 PM
Of course I vent it when temps get above freezing and especially if gets into 50ís.
It's too bad you can't hook up some sort of automatic venting system connected to a temperature thermostat.
It must constantly occupy attention in your mind to have to worry about whether temperatures are going to go above 50 outside during the cold half of the year. That would be too much worry for me.

Kumquat is probably going to be hardier than other common citrus varieties, since it goes into a protective state of dormancy so easily (stays in dormancy).
I'm not sure if this really demonstrates "hardier grown from seed", since I would imagine the span (differential) between kumquat grown on poncirus compared to kumquat on its own roots, and some other hardy citrus grown on poncirus versus on its own roots, would not be as great.

(What I mean is the whole point of grafting a hardy citrus on poncirus is to keep it in dormancy, a trait kumquat already has, to some extent)

Generally kumquat can survive down to zone 8b, so that's already within zone 8 territory.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Citradia on April 16, 2020, 07:06:11 AM
Millet, Iím at 3000 ft elevation on top of a steep mountain, so temps can vary a lot compared to other local areas. Itís not too difficult for me to ventilate my enclosures; I just roll up/down one side of the plastic walls that is stapled to a board at the bottom and hung up on big hardware/bicycle hooks on side of frame.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: Millet on April 16, 2020, 11:32:11 AM
Citradia. I'm at 5,440-ft. elevation.
Title: Re: citrus grown from seed shows more cold hardiness
Post by: poncirsguy on April 16, 2020, 07:30:12 PM
I am only at 500 ft
Title: Re: citrus grown from seed shows more cold hardiness
Post by: SoCal2warm on June 29, 2020, 09:25:51 PM
I will be conducting a specific test over this winter.
The below picture shows two Ichang papeda plants, one on trifoliate rootstock, the other rooted from a cutting on its own roots.

This side by side experiment should be interesting, because I specifically wanted to look at ichangensis and related hardy citrus to ichangensis, and specifically wanted to look at this behavior in zone 8.
Soon we should have a more sure answer whether ichangensis grows better on rootstock or not, when surviving cold climate conditions.
I can provide an update to the results of my test. (as of June 29, 2020)
It seems that both plants have done about equally as well. But the one growing on its own roots has much larger new leaves, in terms of size of the leaves. (I do not believe this is simply due to it getting a head start over the other)
However, they both appear equally vigorous, I would say. The one on the rootstock looks like it has the same energy as the other one, but it is holding back and pacing itself.

The older leaves (from last year prior to the winter) on both do not look very healthy. Still alive and slightly green, but more pale and yellowish.