limiting tree size

[brian]

As of repotting today, my largest tree has reached the limit of my ability to move it in/out of my winter greenhouse, in terms of size and weight.  The root ball had completely filled the ~18" diameter rootmaker pot and is now in one about ~24" diameter.    This is a Home Depot tree so it may not be a dwarfing rootstock.  The original nursery tag is still attached so I may be able to contact them to find out, but regardless it seems to grow and grow.  What's the best way to maintain the current size while still getting fruit?  Cut a third or half way back each year?  Do I need to prune the rootball when using rootmaker pots?

[swimmingfree]

i did not thing those pot cood completely fill with roots how long was it in that pot??? 
swimmingfree

[Millet]

RootMaker air-root-pruning containers stimulate extensive root branching, but the advantages do not last indefinitely. Root branching increases and increases, reaching a maximum, then, if transplanting does not occur, benefits begin to DECLINE. This occurs because there is a limited amount of space in any container, and as that space is filled with roots there is little space for new root development. Plants can run out of space and stagnate, even though there is no root circling. If you do not wish to keep increasing into a larger and larger container, then you can remove the tree from its present container, trim off 5 or 6 CM (2 - 2.5 inches) from the sides and bottom of the root ball then replace the tree back into the original container, and fill the empty space with new medium. There is a common belief that the foliage of the tree should also be trimmed back to match the trimmed root ball.  There is conflicting thought if this needs, or does not need to be done.  Do whatever you think best.  I don't trim back the foliage. The leaves provide support for the development of new roots.  - Millet

[brian]

Here's a thread with pictures of how fast it filled up:  http://tropicalfruitforum.com/index.php?topic=10421.0

Thanks for the info, Millet.  Because I increased the pot size by ~6" this season I will leave it alone until next spring then try pruning the roots only, unless it gets too tall to fit in the greenhouse. 

Just out of curiousity... in a hypothetical example... if you cut off half the roots, what would you expect to happen to the foliage?  Decline across the whole tree?  Just newer or older growth?

[Cassio]

Here's a thread with pictures of how fast it filled up:  http://tropicalfruitforum.com/index.php?topic=10421.0

Thanks for the info, Millet.  Because I increased the pot size by ~6" this season I will leave it alone until next spring then try pruning the roots only, unless it gets too tall to fit in the greenhouse. 

Just out of curiousity... in a hypothetical example... if you cut off half the roots, what would you expect to happen to the foliage?  Decline across the whole tree?  Just newer or older growth?

I have small experience doing this but, here it goes.
Recently I had to prune roots of a citrus (1,20 meter tall) that I have in a container (60 cm tall, 60 cm in the "mouth", 40 cm basis), but branches and leaves weren´t pruned. After to put the tree in the same container, I noted the growth "frozen" for 50~60 days. After that, new leves begun to sprout.
In other case, I pruned the roots of an acerola tree (1,50 m tall), and pruned the branches too. Later, I placed her in a larger container. After 30~40 days, new leaves and branches are sprouting.

[Pancrazio]

This is pretty much what people do with bonsai and since bonsai are kept in pot for centuries (and some species are much worse adapted to pot growing that citrus) seems reasonable that it must works also for citruses.

It has been quite some time since i last grew bonsai and i was a pretty novice gardener back then so my words should be taken with a grain of salt. However, as soon as roots are pruned, i have always hear that leaves should be pruned in equal proportion.
Personally, right now, with a reasobale degree of certainty, i can tell you that if your reduce the canopy of a tree till the 30% you shouldn't see any decrease in vigour. This is, also, i imagine, the upper limit of root pruning.

[brian]

Thanks, guys.  This is great news. 

While I'm not exactly sure how to go about pruning when the roots are in a perfect cylinder, I will figure that out next year.

[Icemankfc]

Brian, it's not a difficult process.  I would suggest to do exactly as Millet suggested.  Don't remove too much or the tree could loose too much sap, strength and you could loose it.  It would be like taking 1/2 of your blood and expect you to recover.. you may, you may not.  You see?
I have a short video how I prune mine and it's the same species.   I root prune in the early spring too which seems to ensure better success. Looking at your tree if you wanted to reduce the size I would do that at the same time I cut the roots back.   Never take away more than 25% of the total roots as a rule of thumb. You can do more but then you need to make other accommodation for follow up care.  Here is a short video of the process you might like, you'll recognize the lime too      https://youtu.be/nzNZEH0NOEU   

[robbyhernz]

Thanks for the video Iceman!! It's comical to see how you rough-handle those roots and I give them the white glove treatment, separating each root individually as to not damage any of them, yet your tree is so much healthier and nicer than mine!

Very instructional video and much appreciated.

[gunnar429]

has anyone addressed the idea of limiting for size while still getting fruit?

[brian]

My tentative plan is to lop off one major limb per year.  I'm not sure how well it will work.

[mksmth]

My tentative plan is to lop off one major limb per year.  I'm not sure how well it will work.

that is a pretty common pruning practice with apple trees.  Any limb 1/3 or larger than the trunk gets pruned. Not sure how well it will work with citrus. You could be the first person to actually compare apples to oranges.   I dont know if I would remove whole limbs as much as I would just keep the overall canopy at a certain size.  Im about in the same situation you are as mine are in 15 and 20 gallon pots now and getting heavy.

[Icemankfc]

robbyhernz - The lime's always bounce right back.  Just try to remove about a 1/4 of the root ball/ root mass.  Again, try to time it right when they're waking up after the winter.  I give them a 'hair cut' LoL!   After a few weeks they'll start growing like weeds again.  Here is a recent photo of the same tree. I use to keep a lot of bonsai and I'm just comfortable cutting them back.  I use to do just like you mentioned too... one at a time.  This photo was taken at the beginning of June and you can see how much it's grown.  I measured it last week and almost 8ft wide and about 7.5ft tall! I have to get it through a door passage so time to cut some of the new growth back again.

[laidbackdood]

I read somewhere that it is good to root prune every 3 years with a bread knife 2 to 3 inches all around the rootball.....remove any dead looking roots.....then refresh with new medium and trim top a bit as well........then dont feed until you see new growth.................when i transplant now....I dont feed at all when i transplant(except seasol to give roots a boost) and then feed 4 to 6 weeks later...
I have just transplanted a lot of my trees into bigger pots at the end of June.......we have July left and then spring will start mi
d august........I will begin my feeding program mid august....so all my transplants have had 6 weeks to settle in through winter( we are talking australia here).......I have done this with all my citrus...both in pots and inground..I try to form 4 or 5 main branches for each tree and open up the middle to let light and air in.......Hopefully this year i will be able to share some successful photos.....my strawbs and chillis in pots have also been transplanted like that.....a few of my citrus are putting out new growth....even now........temps vary from 19C to 23C winter highs but its raining nearly every day at the moment in Perth.
Nice looking tree dood 

[laidbackdood]

My tentative plan is to lop off one major limb per year.  I'm not sure how well it will work.

that is a pretty common pruning practice with apple trees.  Any limb 1/3 or larger than the trunk gets pruned. Not sure how well it will work with citrus. You could be the first person to actually compare apples to oranges.   I dont know if I would remove whole limbs as much as I would just keep the overall canopy at a certain size.  Im about in the same situation you are as mine are in 15 and 20 gallon pots now and getting heavy.

I was reading  an article about growing citrus in pure perlite in isreal.........they use coarse on the bottom and then finer stuff for the growing part........no mix of any kind.......it cuts down on the weight........you could remove a lot of the mix and go heavy on the perlite with new potting mix and that would bring the weight right down and make your pots easier to move.........I will see if i can find that link as it makes for fascinating reading.....how they have these big citrus growing in big see through pots but without thee weight.
Here you go......have a read
http://www.schundler.com/israel.htm

If i am feeling brave i might give this a go with a dwarf Citrus tree using a plastic pot.