When is the best time to root prune and repot potted mangoes?

[starch]

I am thinking ahead here. I have some mangoes in pots and I am planning on keeping them in pots. These are some Manila seedlings from LaVerne that I bought a couple of weeks ago. And I already up-potted them to 5 gallon (actual 5 gallon buckets, not #5 pots) containers that I primed with MicroKote. So at the moment there is no issue with roots and it will be a year or two before I have to worry about the root system running out of space. Next year these seedlings will be topped and I will top-work them with compact mango cultivars.

I am projecting a couple years down the road. As Rob points out below, these will eventually need to be up-potted to stay productive. I did a little more digging around and it looks like 18-20" pots (15-20 gallons) can support a productive mango tree in a pot. So there will be some up-potting in my future. But eventually I will reach that size, and then I will want to maintain it at that size.

I was doing some research and it seems like many people say that repotting and root pruning subtropicals should occur in the spring a few weeks before the major spring growth push. However, I vaguely remember reading that Jeff / Cookie Monster saying (and I didn't bookmark it and can't find the post right off, so this might not be a real memory) that repotting should occur in late summer / early fall after harvest when you do your canopy pruning. That you should do any root pruning then too because the mango roots will respond to the warm temps and bounce back very quickly.

Based on your experience: When is the best time to root prune and repot (not up-pot) potted mangoes? Before spring flush? Or in fall after mango harvest?

[bsbullie]

You will not be able to keep them in 5 gal pot or buckets, whether root pruned or not (if you are doing true bonsai then it should not be discussed gere as this is not a bonsai forum).  No matter what you topwork with, the trees will need to be in a much larger pot.  Butchering a small rootball will lead to nothing good or productive, unless you are just "trying" to keep an ornamental mango alive.

[starch]

I understand the point you are making, and no my goal is to not make an ornamental bonsai mango.

What is the minimum pot size that you would suggest to have a productive containerized mango?

[starch]

It looks like people have been growing productive mangoes in 18-20" pots (so something like 15-20 gallons).

[TnTrobbie]

I have some that are miserable and scraggly in 25 gal pots. Minimum? 45 gal. Ideal would be 65 gal and up.

[NewGen]

I have some that are miserable and scraggly in 25 gal pots. Minimum? 45 gal. Ideal would be 65 gal and up.

I've seen pix of  puglvr's potted mango trees, with fruits, and  the containers are more  like 15-gallon. She IS in southern FL, though, so  that may be  a factor also.

[bsbullie]

I have some that are miserable and scraggly in 25 gal pots. Minimum? 45 gal. Ideal would be 65 gal and up.

I've seen pix of  puglvr's potted mango trees, with fruits, and  the containers are more  like 15-gallon. She IS in southern FL, though, so  that may be  a factor also.

Nancy, puglvr, is not in Southern Florida,  more like Central Florida. The trees that may be in 15 gallon pots and fruiting are very young trees and are being stunted by being kept in that sized pot and let to fruit at that size.  It will ultimately lead to a problematic tree.  I dont understand why people dont understand or comprehend what the size of a mature mango tree is.  Even a Pickering or Cogshall will have a significant trunk, one larger than can be contained in a 15 or 25 gal.

Robbie is right, short term minimumof a 45 gal but you will eventually need the likes of something larger than a 65 gal.  These are trees we are talking about, not shrubs.

[starch]

I have some that are miserable and scraggly in 25 gal pots. Minimum? 45 gal. Ideal would be 65 gal and up.

Hey TnTrobbie,

Which ones in 25 gal pots do you have that look scraggly?

[starch]

Nancy, puglvr, is not in Southern Florida,  more like Central Florida. The trees that may be in 15 gallon pots and fruiting are very young trees and are being stunted by being kept in that sized pot and let to fruit at that size.  It will ultimately lead to a problematic tree.  I dont understand why people dont understand or comprehend what the size of a mature mango tree is.  Even a Pickering or Cogshall will have a significant trunk, one larger than can be contained in a 15 or 25 gal.

Robbie is right, short term minimumof a 45 gal but you will eventually need the likes of something larger than a 65 gal.  These are trees we are talking about, not shrubs.

So if we are talking 45-65 gallon pots, how do you root prune the tree to stay in the pot? It seems like that would become a very large tree (like as you say above, most mature mango cultivars are massive trees). Would that become an impossible endeavor? If you can't pull it up to root prune it, do you just accept that you will eventually lose it to root girdling?

[Rob1977]

If it helps at all I have a potted lychee in a 20 gallon pot. I believe I will eventually run into the same issues a mango tree would.  My plan of attack is every 2 years root prune and top prune the tree right after harvest. This tree was a 2 year old when I bought it in a 10 gallon pot. I potted up to 20 gallon right after I bought it. That was 2 years ago so this coming season will actually be the 3rd year in a 20 gallon pot. I pruned it hard after last fruiting season and it really responded well with new growth. I think the main thing is to balance the top and roots when doing this and water water water! My lychee gets watered daily except for winter.

Now I think the biggest question is how long will one be willing to take on this task while realizing that all this effort will only yield a handful of fruit each season? Will the tree live to a ripe old age? Probably not but if you love to grow stuff, a good 6-10 year run of exceptional fruit and fun growing is all worth it. The trick is to have enough plants and resources to make it worth your while. By resources I mean automatic watering systems, good quality water like rain water, a strong back and the will. All that effort can be for not if something happens and those 5 year old mangos don't get watered for a few days in the heat of summer. We've all done it.

[Rob1977]

[Mark in Texas]

Use a root tip pruning system such as MicroKote, Griffin's Spin-Out or RootBuilder or RootMaker pots.  You will still need a large pot but not near the size if doing conventional rooting.  Regarding timing for upcanning, usually when foliage pushes so does the root system.  So just before or at the beginning of a new foliar flush, upcan.

done........

Question for those growing trees upside down or sideways.  How in the hell do you do it?   

[TnTrobbie]

I have some that are miserable and scraggly in 25 gal pots. Minimum? 45 gal. Ideal would be 65 gal and up.

Hey TnTrobbie,

Which ones in 25 gal pots do you have that look scraggly?

At the moment, LZ and Dupuis. Dupuis is doing surprisingly well with it's growth being bushy (not normal) but it is going to hit its growth limit soon. I Had to re-pot a Philippine this summer as it started to decline in its 25 gal. Got it as a huge 7 gal 2-3 yrs ago and its bore fruit (4-6) each year. Going with a slower or compact growing cv may buy you some time before a re-pot is need, but in the long run you're going to hit a wall in tree growth and health. The Cookiemonster (Jeff) told me the same thing some years back before I attempted this. Turned out to be true.

[starch]

If it helps at all I have a potted lychee in a 20 gallon pot. I believe I will eventually run into the same issues a mango tree would.  My plan of attack is every 2 years root prune and top prune the tree right after harvest. This tree was a 2 year old when I bought it in a 10 gallon pot. I potted up to 20 gallon right after I bought it. That was 2 years ago so this coming season will actually be the 3rd year in a 20 gallon pot. I pruned it hard after last fruiting season and it really responded well with new growth. I think the main thing is to balance the top and roots when doing this and water water water! My lychee gets watered daily except for winter.

Rob,

That is a good looking tree! So have you pulled it out of the pot and done root pruning in tandem with your harvest/pruning (which I gather is the best time to prune lychees)?

Now I think the biggest question is how long will one be willing to take on this task while realizing that all this effort will only yield a handful of fruit each season? Will the tree live to a ripe old age? Probably not but if you love to grow stuff, a good 6-10 year run of exceptional fruit and fun growing is all worth it. The trick is to have enough plants and resources to make it worth your while. By resources I mean automatic watering systems, good quality water like rain water, a strong back and the will. All that effort can be for not if something happens and those 5 year old mangos don't get watered for a few days in the heat of summer. We've all done it.

I really like this philosophy and this is kind of where I am coming from. Thanks for sharing!

[starch]

At the moment, LZ and Dupuis. Dupuis is doing surprisingly well with it's growth being bushy (not normal) but it is going to hit its growth limit soon. I Had to re-pot a Philippine this summer as it started to decline in its 25 gal. Got it as a huge 7 gal 2-3 yrs ago and its bore fruit (4-6) each year. Going with a slower or compact growing cv may buy you some time before a re-pot is need, but in the long run you're going to hit a wall in tree growth and health. The Cookiemonster (Jeff) told me the same thing some years back before I attempted this. Turned out to be true.

I see what you mean. I don't mind hitting a wall in tree growth (Cutting back the tops and roots to keep the tree invigorated, but still controlling the size). But the trunk will keep growing every season and I can see what you mean about this leading to health issues.

[Guanabanus]

Root pruning all surfaces of the rootball before re-potting or planting into the ground is what is supposed to happen (not cutting deep into rootball), to remove circling roots of all sizes.  Nurseries that couldn't be bothered to do this produce plants whose roots form concentric wood-donuts--- a wood-donut for each size of pot that the plant was in.  Storms often uproot and expose these.

Good nurseries re-pot mangos on any day in which the business-hour temperatures are not expected to be below 55-degrees Fahrenheit.

[bsbullie]

Root pruning all surfaces of the rootball before re-potting or planting into the ground is what is supposed to happen (not cutting deep into rootball), to remove circling roots of all sizes.  Nurseries that couldn't be bothered to do this produce plants whose roots form concentric wood-donuts--- a wood-donut for each size of pot that the plant was in.  Storms often uproot and expose these.

Good nurseries re-pot mangos on any day in which the business-hour temperatures are not expected to be below 55-degrees Fahrenheit.

I totally disagree with your first paragraph.   If the root ball has not become bound where there is no girdling, cutting of the roits are not recommended.

[Mark in Texas]

Purchased from PIN and upcanned to a large root pruning pot I failed to catch this spin-out.  It killed the tree after about 2 years.  I will replace this Pickering mango but will knock off all soil before upcanning it and do some surgery if required.  You don't want any girdling, spin-out or J rooting.



I'm in the camp of "less is more" regarding removing any roots.

Mark

[Guanabanus]

Even hair-thin roots that are circling must be removed.  Only root tips can change direction.  A thin circling root can not re-position itself like a snake in the soil after potting up or planting in the ground.   A circling root will only get fatter and fatter, and then woody.

So a plant that in no way seemed pot-bound when un-potted, will, in effect, become pot-bound later, in the absence of the pot, because someone thought it un-necessary to root-prune it, because of reasoning that it had "not been in the pot too long."

[bsbullie]

Even hair-thin roots that are circling must be removed.  Only root tips can change direction.  A thin circling root can not re-position itself like a snake in the soil after potting up or planting in the ground.   A circling root will only get fatter and fatter, and then woody.

So a plant that in no way seemed pot-bound when un-potted, will, in effect, become pot-bound later, in the absence of the pot, because someone thought it un-necessary to root-prune it, because of reasoning that it had "not been in the pot too long."

Unnecessary cutting of roots can also harm the root system and have possible ill effects on a plant/tree.  Guess we will agree to disagree.. To each their own...

[Mark in Texas]

Being a Christmas tree grower and vineyard owner, greenhouse manager and having literally planted thousands of trees out of mainly liners and 1 gal. pots, I usually have no problems by turning the pot/liner upside down, giving it a bump and going directly into the ground. 


If spin out is evident or suspected I will take a very sharp knife or box cutter and score the rootball top to bottom, 4 times around, 1/2" deep, which cuts or breaks up any kind of root spin out. It doesn't seem to effect the vigor or health in a negative way.

Your goal is to allow the tree to grow roots in a bicycle spoke radiating pattern. That's the beauty of root tip pruning systems, you can usually avoid any future problems by using them.