Hello Jim,
interesting posting.... This comes close to what several others told me... but, in containers, we often forget, that the plant is not in ground an got different conditions, but some effects will still be compareable...
Thanks for that posting, but I need further time, to understand fully.

Dear Millet,
thanks again for you posting. Let me give some comments.

Quote:

Although, a few people want huge trees and therefore use Volkameria, Swingle, and perhaps Carrizo, door yard growers much prefer smaller trees, that still produce high quality fruit.

Well, even Carizzo and Volkameriana make very nice rootstocks for container grown citrus, and because of the better and idividual care, the less fruit quality will not become that severe as in commercial found groves and the same stocks.
Also, the higher vigour will impart much more growth of the trees, but by prunning those trees will still even be controlable and will endure very good in containers. If you like, I can show you a nice picture of my Nules Clementine and an Nagami Kumquat, both on Citrus macrophylla... Well, both trees have a huge size, for many container growers, but if you want smalller trees, only the stem has not to be forced that size, and it remains smaller.
Usually most Lemons in the shops over here are grafted on Sour Orange, and even this intermediate vigour makes nice pot plants, and my own experience shows, that even other roostocks do well in containers.

Quote:

In the USA smaller dwarf trees are now becoming quite popular among commercial growers.... because small tree size allows a higher tree number, or density, per acre, fewer IF ANY hedging and topping (pruning) cost., and MUCH EASIER FRUIT HARVESTING on smaller trees.

Of course on first hand, that seems to be true. But what about long term investigations on such ochard behavior?
Well, I think: If the growers want do this, they should go on. It's teir decission, their option, their choice!

Quote:

Steve, in my opinion, European growers need to ketch up on grove technology.

Realy? Wouldn't this be to dictate something, rather than to give them their own option and let them do their own decissions?
Because on many groves I found trifoliate plants won't do well, and even if you save cost by less hedging and topping, you have to pay more for special nutrient managment, because often here trifoliate stocks will be grown on their tolerance limits within soils....


And for our container growers, I think, they should start thinking about rootstocks in different ways, because mostly they pay not attention to the rootstock characteristics.. but if you know, you can makee your culture more easily. And that means:
There is no rootstock for everyone, there is only a decission personally for everyone of us.

And we should not blame anyone for his choice, or dictate him one. <- Hope you will agress in this last sentence....

Interesting discussion.
For reasons beyond my understanding of citrus, I have a slow growing 7 year old PT bush in my front yard. I don't know why its so slow growing, yet 15 feet away is another PT (the scion died last winter) this plant pushed out lots of new growth , perhaps 10 branches of over 18" of new growth each.
On the same token a Juanita tangerine (in ground) on PT is growing very slowly yet my Changshas also on PT grow at a much much greater rate.
I am not sure if it is the genetics of each PT parent or not. I would like to get my Juanita budded onto Carrizo to see if that will make a difference.
Greg.

gregn,
there are so many reason for those different behaviours....

I have made the same experiences, and because to attain more uniform growth, I switched to other rootstocks, and it worked, for me.

So maybe you have different rootstock selections of Poncirus.
I use a special variety from a friend. He collect at Frankfurt, and it's somewhat more vigouros with larger fruits, as the selection I used before.

But, I abandoned it as rootsock fpr my containers... because it did not fit for my culture.

Steve wrote,............("Sometimes they have weeks of only 42° F daytime temp and down to 33° F of night temperature.")........ Steve, I'm sure you are correct, and I am aware of those types of temperatures in that area. I was not writing about AIR temperatures. If you re-read my post you will see I was talking about SOIL temperatures. There is a huge difference between the two. -

Greg, Juanita is a mandarin, and your Juanita was grafted onto PT, therefore, perhaps due to a possible graft union problem, which are reported quite frequently, with mandarins that are grafted onto PT stocks, may or may not have something to do with the trees problems. The other tree you were talking about that was so slow growing, you did not mention what the slow growing scion variety was. - Millet

Millet, the slow growing PT is just that. No scion on it. The trunk is about 1 1/4" in diameter , 3' tall and 2' in diameter. Perhaps one day it will bear fruit . I need the seeds for my own production. (then again, this may not be a good specimen to draw from )

For those of you who attend the Citrus Expo, you will hear from Carl Heatwole, a South Carolina farmer and dairy owner, who has a small grove of Satsumas planted near Olar, SC. All of the trees are on Poncirus trifoliata 'Flying Dragon'. Carl followed the recommendations of Professor Arlie Powell, Extension Horticulturist, for AU, who specializes in citrus. I believe Professor Powell will be at the Expo, and I am sure he will be glad to discuss the advantages/disadvantages of Poncirus as a rootstock. With a little luck, he will be on the panel of experts. I know Carl will have plenty of slides to share with us.

http://www.aces.edu/pubs/docs/A/ANR-0603/

Carl also has a collection of various other citrus at his farm.

Greg, I have had some reservations about Juanita on Poncirus myself, but I suspect they are ok on it. No way to really know though, but it is thought that Juanita is a seedling of Dancy, and I as far as I know Dancy is grown in trifoliate without problems. I have put Juanita on seedlings of Thomasville, and it has done very well on that rootstock so far. Good vigor and a sound union at the graft. I have no reason to think will not be ok on Thomasville on a long term basis. Given Thomasvilles parentage, I would think it will perform well as a cold hardy rootstock.

Greg, One thing you might want to try with your poorly performing is to inarch another rootstock to the tree. This is a fairly easy thing to do, because both plants are on roots that will support them through the process. I saved an Ambersweet that I had put on a poorly performing rootstock this way.

http://i150.photobucket.com/albums/s88/NedsPhotos/2007June30Plants_20070620_0004.jpg

Ned

Steve, no I do not think that lower temperatures for several days will have much of any effect at all on soil two inches or deeper below the surface. Most especially, I cannot believe it would be possible at levels of feet below the surface. Dirt is a very good insulator.

Ned, then the Procimquat, that I recently purchased from you, is growing on Thomasville? BTW, this summer I have purchased 5 trees from Ned, and all of the trees were very healthy and very nice trees. As a bonus, on the last purchase, a Procimquat, I even received a little free Spanish Moss and at no extra charge.

I met Dr. Arlie Powell at the Charleston, SC 2005 Citrus Expo. Dr. Powell is a wonderful and extremely knowledgeable man. BTW Dr. Powel is also a good friend of Bonnie Childress. Unfortunately, due to a late plain arrival at O'hare airport in Chicago, I missed my intended side trip to Mr. Heatwole's new grove. I hope to visit his grove during this year's trip to the Akin, SC Citrus Expo. - Millet

I think this thread has become a bit of a cultural thing. Steve has quite a bit of experience growing citrus http://www.steffenreichel.homepage.t-online.de/Citrus/index.html in his location as does Millet in his location.

I know we all have different views on things & don't mean to come off the wrong way. Please have respect for each others opinion.

This forum was created because GW became such BS. Everyone is welcome to their opinion, but please keep it civil.

Laaz, it seems civil enough for me, but if you think there is a problem I will drop out of this thred. - Millet

Bob, The procimequat is a seedling. They do fine on their own roots. Primarily, I have only done the Juanita and Thomasville on the Thomasville rootstock. I have done a few others, just to see how they would grow, and everything has done fine so far. Like two of it's parents, Thomasville goes "dormant" (got to be careful how I use that word here!lol) early and breaks dormancy late. I hope that characteristic will manifest itself in the scions.

Bob I can load you down with spanish moss! My Dad use to make me pull it to feed our two cows. He even had a special, homemade moss puller. I am not sure it did anything for the cows, but they loved it. Didn't seem to affect the taste of the milk.

About ground tempertures, I was almost certain that the soil temperture dropped in the winter. For some reason I was under the impression it sometimes gets down to like 45 degrees f. here. I am going to have to ask our County Agent. Don't they plant crops, at least in part, according to soil temperture? Isn't this something farmers watch? I know our well water stays a constant 55 degrees year around.


Ned

Lazz,

I just read your post. I have edited my post, and removed my comment regarding the strong feelings being expressed in this thread. I would say things have become less intense since then. I would just add that everyone should respect each other's feelings and keep comments focused on the subject being discussed. Sometimes we forget that in the heat of debate. This forum should be a place to share information, meet with friends having a common interest.

Ned, yes I would agree with you that soil temperatures can drop as winter lingers, but in a cold spell of a few days like what might happen in sub-topical countries, I don't think so. Also, yes your correct about farmers, we plant our winter wheat according to soil temperature. - Millet OUT

Ned, Surface soil temps do change with the season, but the deeper you go the less change there is. As you mentioned, your well water is always 55. Here I think I have heard or read that our deep soil temp is pretty close to 68 year round (spring fed creek water is close to that temp). I do not know the depth where soil temp is constant, but I do not think it is much more that a foot.

As for the discussion on rootstocks, as a homeowner, what would matter most to me is disease resistance, fruit taste, and productivity to meet our needs. Excess growth that requires pruning would be a negative, but would be acceptable if the rootstock provided significant advantages in any of the above categories.

Cold tolerance is a benefit if it exist, but in the case of the real killer freezes that we can get here (10 F) is unlikely to matter much. Marginal difference can be obtained by microclimates and protective measures.