Author Topic: How to pick the perfect rootstock, and where to buy it?  (Read 1233 times)

Olivier

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How to pick the perfect rootstock, and where to buy it?
« on: March 04, 2021, 02:48:59 PM »
I have been obsessing with US-942 lately as it seems to be the 'best' rootstock at the moment. High yields, resistant to many diseases and produces great quality fruits. And based on some numbers I saw online, it seems like Florida growers have been shifting to this rootstock over the past few years.

That being said, I have no clue if having that rootstock will make any difference for the environment in which I grow.
-All my trees are in pot. I have no opportunity to plant them in ground.
-They grow indoors from September/October to May
-Outdoors during summer
-Trees need to remain small (less than 6ft tall and I'd say max 3-4ft wide)

Am I driving myself nuts for nothing chasing the US-942? If not, if it's really worth it, where can I buy seedlings or seeds?

brian

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Re: How to pick the perfect rootstock, and where to buy it?
« Reply #1 on: March 04, 2021, 05:27:25 PM »
the lazy way is "order trifoliate orange seeds from ebay/etsy/this forum" and grow them.  My personal experience is that rootstock isn't the most important factor, temperature, drainage, and watering is. 
I haven't tried growing any other rootstock, though I have had trees of various rootstocks growing in containers.   If your trees get too big consider yourself succesful :)

When that started happening to me I graft them onto flying dragon (dwarfing) and I will eventually toss the donor trees (which are mostly on C-35, and other rootstocks I don't even know)

If you are growing in containers in the north your trees will be dwarfed anyway to some degree.  I've definitely had container trees get 6ft+ tall, but it took a while.  In-ground trees grow like 3x faster for me, though (in a heated greenhouse)
« Last Edit: March 04, 2021, 05:32:55 PM by brian »

lebmung

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Re: How to pick the perfect rootstock, and where to buy it?
« Reply #2 on: March 04, 2021, 06:19:41 PM »
there is no perfect rootstock.

For Canada I would use sour orange for pots, poncirus slow downs the tree in winter even under grow lights.

poncirsguy

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Re: How to pick the perfect rootstock, and where to buy it?
« Reply #3 on: March 04, 2021, 11:10:20 PM »
My Fukushu on Flying dragon is slow right now.  My New Zealand on Seville sour and another NZL on US897 will grow all winter under lights.

Olivier

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Re: How to pick the perfect rootstock, and where to buy it?
« Reply #4 on: March 05, 2021, 07:55:36 AM »
Thank you all for your answers, I appreciate it.

If you are growing in containers in the north your trees will be dwarfed anyway to some degree.

I was under the impression a tree would produce better quality fruits the closer it gets to its full potential/maturity. That is based on some thread I read here about grapefruit trees. I don't know if it applies to all citrus though.

Assuming the above statement is true, I'd like to get a tree that is meant to be relatively short.

My Fukushu on Flying dragon is slow right now.  My New Zealand on Seville sour and another NZL on US897 will grow all winter under lights.

I have one tree on US897 and it barely grew this winter, but the tree seems to have been mistreated in the past (weak trunk with scars) so it's probably not a good benchmark. Among the trees I have, those grafted on KH (couldn't figure what rootstock that is) are doing the best in terms of growth.


For those of you who graft trees on a regular basis, where do you obtain your rootstock? I can find Flying Dragon, Trifoliate Orange and C-35 rather easily, but the USDA rootstocks (US-xxx) seem to be reserved for wholesellers. I must have contacted 15 nurseries in Florida so far and no luck yet.

citrange

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Re: How to pick the perfect rootstock, and where to buy it?
« Reply #5 on: March 05, 2021, 08:02:05 AM »
Quote
Am I driving myself nuts for nothing chasing the US-942?
Yes!
A rootstock chosen for best commercial use for Florida is irrelevant to growing in pots in Montreal.
You have completely different climate, soil type and likely pests and diseases.
There is no published research on rootstocks for your conditions because there is no commercial imperative to carry it out.
You should consider the following points.
Tree size in pots is controlled mostly by the size of the pot.
If there is any danger of frost, choose a Poncirus trifoliata rootstock - but presumably in Montreal you keep heated in winter so that's likely irrelevant. However, it may be best against phytopthera root rot which can be a problem in cool conditions.
With possibly low light conditions in winter a vigorous rootstock might be best to get good growth for the months when possible. Most citranges and citrumelos are vigorous and root rot resistant. Here in UK, I find Rough Lemon good if you ensure excellent drainage. You will read that fruit quality is not the best, but at least it does produce results in imperfect citrus climates.

brian

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Re: How to pick the perfect rootstock, and where to buy it?
« Reply #6 on: March 05, 2021, 10:22:56 AM »
Yes, I think your results will be weighted much more by your personal care and conditions than the rootstock's attributes.  I think as long as you don't use rough lemon or one of the super vigorous types you should be fine with whatever you can obtain.

Millet

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Re: How to pick the perfect rootstock, and where to buy it?
« Reply #7 on: March 05, 2021, 11:39:42 AM »
>>>Olivier wrote: I was under the impression a tree would produce better quality fruits the closer it gets to its full potential/maturity.<<<

The above sentence is true.  Citrus trees don't start producing higher quality fruit until they approach an age of 5 years.  After that the older the tree becomes the better the fruit quality.  I have never forgotten a post by Dr. Malcolm Manners when he wrote "the best grapefruit I have ever ate, was a March Seedless grapefruit, pick off a 25 year old tree.

Tree age = increase fruit quality.

Olivier

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Re: How to pick the perfect rootstock, and where to buy it?
« Reply #8 on: March 05, 2021, 12:32:20 PM »
Millet, thank you for your reply. That quote from Dr.Manners is exactly what I was referring to.

Does the age itself increase fruit quality? Or does the age also implies tree size?

In other words, would a 25 year old tree that was kept small produce the same fruit quality as a 25 year old tree that was fully grown?


@brian and citrange

It looks like you have different opinions on the rough lemon. I'm curious to know what would be the pros and cons?

Millet

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Re: How to pick the perfect rootstock, and where to buy it?
« Reply #9 on: March 05, 2021, 08:48:55 PM »
Olivier wrote   >>>>>In other words, would a 25 year old tree that was kept small produce the same fruit quality as a 25 year old tree that was fully grown?<<<<<

Olivier, great question.. A citrus fruit does not draw all its required nourishment/energy from the entire tree, to grow from a flower into a mature fruit. Every thing the fruit needs for development comes only from the 3 to 4 closest leaves to the fruit.   Therefore, I don't think the tree size has much to do with it.
« Last Edit: March 05, 2021, 08:50:34 PM by Millet »

Galatians522

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Re: How to pick the perfect rootstock, and where to buy it?
« Reply #10 on: March 05, 2021, 11:18:32 PM »

I have one tree on US897 and it barely grew this winter, but the tree seems to have been mistreated in the past (weak trunk with scars) so it's probably not a good benchmark. Among the trees I have, those grafted on KH (couldn't figure what rootstock that is) are doing the best in terms of growth.


For those of you who graft trees on a regular basis, where do you obtain your rootstock? I can find Flying Dragon, Trifoliate Orange and C-35 rather easily, but the USDA rootstocks (US-xxx) seem to be reserved for wholesellers. I must have contacted 15 nurseries in Florida so far and no luck yet.
[/quote]

KH should be Kuharski. If you are really set on US-942 maybe you could purchase a tree grafted on that stock and remove the scion so that the tree could sprout from the rootstock. You should then be able to take cuttings or air layers (which are more reliable for some people) to propagate as many rootstocks as you want.