Use of Swingle 5 Star as a rootstock?

[till]

Hello,

I got Swingle 5 Star from Ilya a few years ago and made the experience that cuttings can easily be rooted and plants have robust roots, the form of which is much like Poncirus (no taproots, well branched). The potted plants never suffered from male nutrition or root rod as did many others. They were more healthy than several Poncirus seedlings. So I am considering to regraft many of my weaker citrus plants, especially those on sour orange rootstock, to Swingle 5 Star. I also made good experiences with Swingle Citrumelo, but Swingle 5 Star is more appealing to me because it is verygreen.

What experiences did you made with Swingle 5 Star as a rootstock? Have you discovered any incompartibilities? How pronouncted is the elephant leg phaenomenon? 

Regards,Till

[ilya11]

It is excellent rootstock but I do not have much experience with its rooted cuttings. Its seedlings have very profound taproot that improves the inground freeze resistance. I have not noticed any incompatibility with mandarins. I also has its nucellar seedling that is even more vigorous.

[till]

That is good news, Ilya. I feared it was incompartible with mandarins. What experiences did you made with lemons? How pronounced is a neck at the graft union - I mean the phaenomenon known from Poncirus that the understock becomes much bigger than the grafted variety?


I have tried to root some twigs. I cutted them in winter, put them into small pots with normal loamy garden soil, and placed them indoors under a plastic bag. I did not use rooting hormone. I cannot remember a cutting that did not root. Some were faster than others but finally all did well.

[ilya11]

I never grafted lemons on it,  "elephant leg" in the case of mandarins is absent.

[millet]

I have most of my trees grafted on poncirus, and most have developed what Ilya calls "elephant leg", None of my trees has ever experienced a single problem.  Some are going on 20 years old.

[david]

Benching is a normal process with poncirus or FD. It is not detrimental to bloom, fruit production or fruit quality. Its worth the unsightly appearance of benching for a the good things poncirus does as a rootstock.

[till]

Thank you for your replies! My experience with Poncirus is in general also good.

But I had difficulties in grafting Moro orange on it. The bud easily growed together with Poncirus. But I got no shoot in spring. In warm spells, the Moro bud growed but in cooler spells the rootstock dropped the immature twigs. In the next warm spell Moro grew again only to drop its twig in the next cool spell. I think it has something to do with the different warmth requirements of Poncirus and oranges. Poncirus grows at cooler temperatures and "feels" that the Moro twig is somewhat ill when it cannot absorb its growth power at low temperatures. So it drops it.

I have also a Fortunella obovata bush on Poncirus with such an elephant leg that the bark will soon be pinched.

Then I see that Poncirus is not like Poncirus. I got many nicely growing seedlings but also a number of seedlings that were susceptible to root rod or were somewhat tender regarding iron deficiency.

Finally, I am searching for understocks with more growth power than Poncirus.

That is why I'd like to try Swingle 5 Star as a rootstock.




Millet, you did also graft lemons on Poncirus?

[david]

Swingle is a good rootstock. Lots more vigorous than poncirus. Troyer & Carrizo are very vigorous and good rootstocks. I find hardly any compatibility clashes with poncirus. I have grafted lots of strange stuff on it and had sucess. Some things I do not graft....let them grow on their own roots. The only real drawback to using poncirus and FD is its extremely slow growth pattern.

[ilya11]

Till, I have never observed any problems in grafting oranges, including Moro on Poncirus. May be your budwood was infected?

Among lemons only some sources of Eureka have problems when grafted on poncirus due to the presence of citrus exocortis viroid.

PT is extremely sensitive to it.

[samodelkin]

Used Swingle for a wide variety of citrus varieties, there are no compatibility issues. Swingle is a great rootstock. It has only 1 drawback - does not tolerate high Ph and calcareous soil, this leads to chlorosis

[millet]

Whether one uses a fast growing rootstock such as Swingle, or a dwarf slow growing rootstock, all depends on what circumstances and location the tree is to be growing in.

[till]

Difficult to say, what exactly was my problem with Moro. But I had a similar problem years ago when I wanted to force a Faustrimedin bud grafted on sweet orange. It was winter and days short. The bud shot again and again but all immature twigs fell off. I suppose lack of light was the reason. My Moro mother plant has no particular signs of disease but never grew well and had yellow leaves from time to time although I repotted it and aplied fertiliser. It came from Italy and I guess it was grafted on sour orange. All my sour oranges suffered from root problems. They cannot handle our long cool winters. (Contrary to literature, sweet oranges do much better here...)

Anyway. Thanks for all replies. I think I should use Citranges and Citrumelos became they grow faster than Poncirus. And I shall continue using Poncirus for really hardy stuff.

[till]

I have to correct myself: Rooted cuttings of Swingle 5 Star tend to build taproots. They have a stronger tendency for deep roots than Poncirus. The root system of my cuttings is in general very strong. The roots develop from a callus knot at the wound (the undermost end), are multiple and in sum definitely thicker than the trunc. They grow in different directions from the callus knot, are well branched but tend to grow deeply.

[Sylvain]

I have a Prague grafted on 5* as inter-stock grafted on poncirus as root-stock. It grows very fast and the graft points are undiscernible

[ilya11]

I have never seen bark splitting on 5* rootstock trunks even after the winters when grafted poncirus  had large cracks.