Colanders: Deciduous vs Conifer vs Evergreen vs Tropical vs Subtropical ???

[just.wing.it]

So, over a couple years I've had so many mixed feelings about colanders/grow boxes/whatever.....

I have read many mixed opinions on colander use with deciduous trees...and others....
One thing I've seen says that colanders on deciduous will help reduce the size of your root ball....
I've also read that it is useless to use colanders on deciduous trees, all together....
I've also read that you should never use colanders on trees with "fleshy" roots, or on Junipers due to their fibrous roots....
And what about azaleas and boxwoods, and other evergreens and subtropicals?
Anyone ever use colanders on a taxus?
Or on Tropical's??

 

[sorce]

Damn....

I have boxwood, juniper, mugo, ulmus, Acer, forsythia, hell....

Everything I have except spruce is in colanders/baskets.
But next year will see those too.

The only thing I can think that would hurt anything....is if you NEED long roots running to fix a Nebari.

Other than that, I see no harm.

Sorce

 

[Stan Kengai]

In my experience, they are great for growing out pines, hinoki, and azaleas. They are good for reducing and or increasing density in deciduous and juniper rootballs, but not optimal for growing these out, with the exception of Chinese quince.

 

[my nellie]

Hello,

I have used pond baskets which were planted into a jardiniere and a grow-box at the balcony. I used them with different species such as juniper, brazilian rain tree, winter jasmine, elm.....
Indeed, the trees were growing vigorously, better than before. Great deal of new hairy roots at repotting time!

 

[Anthony]

Colanders, tropicals and ground [ trough growing ] ----------------- excellent.!
Removal, rest in colander, re-develop fine roots for a few months ------------- happy trees and shrubs.
Good Day
Anthony

 

[Adair M]

Let's figure this out...

What does colander growing do?

It prevents rank root growth, and circular roots. It promotes root "back budding", and keeping fine feeder roots close to the trunk. It does this on "autopilot". That is, you can plant the tree in the colander and leave it for a couple years, which is good for trees that don't like to be repotted very often.

Which trees don't like frequent repotting?

Pines and conifers.

(I have no clue about boxwoods or tropicals. Somebody please inform us about them).

Which trees don't mind annual repotting and barerooting?

Most deciduous trees.

Do we need to use collanders on trees that naturally produce fine, fibrous root systems?

No. They do it naturally, so there's no benefit.

Which trees naturally form fine, fibrous root systems?

Junipers, and azaleas. Probably others as well.

Now, applying logic to all the above, it would appear that pretty much the only species where collanders would have any real benefit would be Pines and other similar conifers, but not junipers.

This technique was developed by a fellow who wanted to grow Shohin JBP. Which would need to be able to be put in small pots. Therefore, he wanted fine feeder roots to remain close to the trunk.

Deciduous trees develop the best nebari by annually repotting and barerooting the tree, working the nebari each time. The Ebihara technique is appropriate to build a spreading flat nebari. To develop a broad deciduous nebari, you do need rapid root growth. Circular roots are just fine because you are going to cut them off within a year. With an air pot, the roots won't grow as much, and development slows.

 

[garywood]

Adair, very good analytical post! Good job clearing up a lot "information" that's out there.

 

[just.wing.it]

Thanks @Adair M
You da man!

 

[Stan Kengai]

@Adair M Good, rational explanation. I'd like to share a caveat I've found with azaleas. We know that azaleas are naturally shallow rooting plants. In the ground, their feeder roots are typically found in the top 2 to 3 inches of soil. In training pots, they grow a nice dense, thick layer of roots near the surface and another thinner layer along the walls of the pot. However, when grown in colanders, azaleas seem to view the walls of the colander as an open surface. Instead of getting a thinner (1/2 inch) layer of roots along the pot wall, you get a 2 inch layer of roots along the colander.

Additionally, azaleas in colanders can be watered along with all your other plants daily without fear of overwatering, which I've had problems with in pots.

 

[MichaelS]

"Adair M, post: 407805, member: 13405"]

This technique was developed by a fellow who wanted to grow Shohin JBP. Which would need to be able to be put in small pots. Therefore, he wanted fine feeder roots to remain close to the trunk.

If we are talking about the same guy, my understanding was that he used colanders so he could remove the tree from it and place it in a larger one without cutting the roots. = no root pruning = faster route to his goal of a fat trunk. Not because he wanted to produce more fibrous roots so he could get the tree into small container. In other words, speed was his motivation.

 

[my nellie]

Adair M, this is really a logical analysis.
May I add though that it depends on the age of the tree.
If you are growing small trees then the colander, air pot, pond basket, or screened pot are all very useful in terms of growth acceleration

... ... Circular roots are just fine because you are going to cut them off within a year. With an air pot, the roots won't grow as much, and development slows.

The age of the tree also applies here. The development by no means slows down because the roots escape from the holes into the soil in the ground/growing box/jardinier/bigger pot (whichever be) and keep on growing. And if the colander, air pot, pond basket, or screened pot is not planted into the ground or into a growing box, jardinier or bigger pot then the physical air-prunning which takes place is providing a good ramification of roots.

 

[just.wing.it]

I have 2 azaleas that I may out into colanders next year.

 

[M. Frary]

I put everything in colanders.

 

[Adair M]

If we are talking about the same guy, my understanding was that he used colanders so he could remove the tree from it and place it in a larger one without cutting the roots. = no root pruning = faster route to his goal of a fat trunk. Not because he wanted to produce more fibrous roots so he could get the tree into small container. In other words, speed was his motivation.

MichaelS, I may have mis-spoke. I really don't know what his motivation was. It may indeed have been speed. But that's not what he got. He got fine, compact root systems, perfect for Shohin.

If the goal is speed, speed in growing a massive trunk, nothing - absolutely nothing - beats growing in the ground! The tradeoff is you're likely to get some roots that are very large and long. And perhaps out of scale. Especially if you are trying to develop a Shohin. Remember, you still have to be able to get it into a small pot!

I think that collanders are great. They work fine in certain situations. But other situations may call for different techniques. Like most all things related to bonsai: it depends! Lol!!!

 

[just.wing.it]

It depends, indeed!
Thanks everyone!

 

[aml1014]

I currently don't have any conifers in colanders, but I do have a collected ponderosa pine in a grow bag that is doing great! I've found deciduous trees to grow slower in colanders for some reason, yet tropicals grow like a weed in them. This is a tiger bark ficus that is 2 years in its colander from a little twig of a cutting, before working on it tonight it was 4 ft tall, and currently has a 1inch trunk. But I decided to set up some airlayers tonight and give it a haircut.
Aaron

 

[Vin]

Which trees don't like frequent repotting?

Pines and conifers.

(I have no clue about boxwoods or tropicals. Somebody please inform us about them).

Boxwoods are slow growers as you know. However, their root systems recovers quickly to heavy pruning and can handle repotting every couple years. Every year may be pushing it and there is really no need for it. They grow well in Grow Bags. I haven't tried colanders but I can't help thinking they would do fine.

 

[fredman]

I put everything in colanders.

Me to. Even the bigger plastic pots are drilled full of holes.

 

[fredman]

Now, applying logic to all the above, it would appear that pretty much the only species where collanders would have any real benefit would be Pines and other similar conifers

Maybe i'm missing something Adair. Why would deciduous trees not benefit from a colander? When I plant them in a pot, they create long circular roots with the finer ones mostly at the ends. When I plant them in a colander, they form finer roots that starts splitting up closer to the trunk. Exactly what we want for bonsai. As I see it, all trees except those that have natural fine fibrious roots, would benefit from a colander.....deciduous and evergreens alike.
What am I missing?

 

[aml1014]

What am I missing?

The different reporting intervals. I repot my tropicals, subtropicals, and deciduoua every 1-2 years at which point we cut off the circulating roots. Where as pines, and junipers are repotted every 3-5 years or more.

Aaron