What are your thoughts on pond baskets?

[Manbris]

My 2 cents.
Pond baskets are cheap and available almost anywhere. I use them frequently and heel the trees in the ground.
The roots do need to be addressed about every two years I feel it’s the next best thing to growing in the ground. You can still easily dig up the pond basket when needed.

Nursery cans only allow escape roots through the bottom holes. Pond baskets allow roots to escape anywhere.

Anderson flats are wonderful but cost a lot more. My big trees get the Anderson flat treatment to help develop a flat radial root system.

is big/small meant by size here? How do you heel it in the ground? If you dig it out does it lose a lot roots? Would that bad for the tree?

What about for developing nebari? Is pond basket still good?

 

[Manbris]

I think they're unsightly especially when the moss and the other green stuff starts growing on the sides. But they're cheap, available everywhere and work well if you understand what to (not) use them for.
I've never seen Andertons flats in any store near me so the choice for me is simple.

How do you use them?

 

[Potawatomi13]

A stupid idea! More plastic junk in the environment. Use Terracotta.

 

[Shibui]

I tried mesh pots - similar to pond baskets years ago but did not get the same rates of development as in normal black plastic nursery pots so went away from anything with lots of holes.
Maybe it is too dry here through Summer. Maybe my potting soil or watering is not right for pond baskets but the trees in them just did not grow well.
You can bury pond baskets in the grow bed so the roots grow through but planting trees direct in the ground achieves the same thing so why bother with the extra plastic?
Air pruning does make roots ramify but that only seems to happen close to the outer edges. I want roots to ramify closer to the trunk. In my experience, the pond basket does nothing for that.

You can use cheap plastic colanders from a discount shop. We call them $2 stores in Australia. I think they're called dime stores in USA. It's the kind of shop that sells a lot of random bad quality stuff cheaply.
Also to note that I have just potted almost all my trees (sticks) into colanders and pond baskets and have found that they are concerningly flexible as Brian Van Fleet said. I feel that every time I pick up a pot (colander) I'm breaking new roots.

Cheap colanders from the $2 shop are cheap but are not UV stable. They have a life of 1-2 years before falling apart when used outdoors. More bits of plastic in the environment!

It seems there are many in favour but I note that the names against so far are all very experienced growers. I think that says something.

 

[oranjeaap]

How do you use them?

Well like others have said, for situations where you want maximum drainage and aeration and have low risk of exposure to weather extremes. For me that means in winter, where it can rain for several days straight and soil dries super slow because of low temperatures and low light, trees that like dry roots can still be happy.

 

[Manbris]

Do no think we have Anderson flats in the UK or EU at least do not see it on eBay. Can the below work?

Also for building wood box, any wood plank will work or pre treated wood?

 

[Lara_Ericacious]

Do no think we have Anderson flats in the UK or EU at least do not see it on eBay. Can the below work?

I've used these crates in the past. However they quickly deteriorate after a few seasons.

 

[Wires_Guy_wires]

My black pond baskets are covered in white lime scale after the first year. I can break chunks off and chalk my hands with them.

I'm not seeing any improvement compared to mesh-bottom pots with closed sides.
Small pond baskets inside bigger pond baskets with a layer of soil separating the two are working well for me. Pond baskets for ground growing seem to do nicely as well; it's easy to cut around them and put them back into the soil. I can't say I'm a huge fan.

 

[Shibui]

Also for building wood box, any wood plank will work or pre treated wood?

Any wood will make a box but be aware that some wood rots quick. Grow boxes are constantly wet and lots of nutrient so the very worst conditions for wood.
Best to use naturally rot resistant timber or treated wood if you want your grow box to last more than 1 season.
Treated timber is no problem for the trees. The chemical treatment affects fungi and wood rotting bacteria but does not affect plants. I've used CCA treated pine for years to build grow boxes. They last up to 5 years and no problems with plants growing in them.

 

[Dav4]

I've used loads of pond baskets through the years and like their utility. They're inexpensive, fit closely together on benches, and, imo, do a fine job allowing reasonable root and canopy growth in younger material. All of my pine seedlings will land in pond baskets and stay there for at least 3 years or longer in the beginning of their development. If destined to be shohin material, many will get moved into a stoneware bonsai pot for further refinement. Projects destined to be larger get moved into Anderson flats. I don't bother using terracotta pots as they fall apart after a few years in cold climates. I've used wooden boxes frequently as well, but they're usually reserved for very large, collected material or bonsai in decline needing some TLC.

 

[BobbyLane]

Op was asking about shallow boxes and trunk development. Check out some of @clem Maple development threads.

I dont use pond baskets anymore, they tend to dry out very quickly on my balcony where it can get very sunny (south facing) and a little breezy.
I love the look of Anderson flats, dont think they ship to UK. I have been using washing up tubs, they work well for me and Im also looking at cutlery trays, without the compartments in, they often make them fairly shallow. Alternative choices to building wooden boxes to size.

Cutlery trays are very cheap and built sturdy

 

[BrianBay9]

They're great if you're willing to water often enough. Here in the summer that means three or four times a day.

 

[penumbra]

FWIW, I have 50 of so pond baskets in partial sun in an irrigated zone. For me, they are a perfect choice and I never need to water more than once a day even in midsummer. The larger ones on the mulch can go sometimes a few days. The smaller ones on the benches get watered about every other day except when it is very hot and sunny, then requiring daily watering. I have never experienced root rot or other similar problems with baskets that I have with regular nursery pots. These are mostly developing trees that have a good amount of organics in their mix, though a number of my pines are in a coarse bonsai mix.
I have learned over the years that there are some plants that do much better in pond baskets. Examples are pines, and ginkgo.

 

[Manbris]

FWIW, I have 50 of so pond baskets in partial sun in an irrigated zone. For me, they are a perfect choice and I never need to water more than once a day even in midsummer. The larger ones on the mulch can go sometimes a few days. The smaller ones on the benches get watered about every other day except when it is very hot and sunny, then requiring daily watering. I have never experienced root rot or other similar problems with baskets that I have with regular nursery pots. These are mostly developing trees that have a good amount of organics in their mix, though a number of my pines are in a coarse bonsai mix.
I have learned over the years that there are some plants that do much better in pond baskets. Examples are pines, and ginkgo.

Very interesting you mentioned Ginkgo- why is it? is it not a water loving plant instead of liking a pine? I also have a Ginkgo in a basket but found their roots are very fine...

 

[Eckhoffw]

is big/small meant by size here? How do you heel it in the ground? If you dig it out does it lose a lot roots? Would that bad for the tree?

What about for developing nebari? Is pond basket

Large meaning trunk and tree size. When I’ve grown out a tree to the point where I feel the trunk is close to large enough, I may repot into an Anderson flat to then work the roots into a shallower/flatter environment.

I heel in Pond baskets for growing out and easy extraction. Then A shallow wooden box/ Anderson’s flat for developing nebari.

 

[NMbonsai]

So the main consensus is pond baskets are definitively better for developing trees as long as you can stay on top of watering. I do have 4 trees in pond baskets currently but was wondering if there was any downsides to it. They are growing pretty well but all have 0.5 in trunks so not sure if I should keep them there or switch to something else. I expect them to be growing out for maybe 5-10 years so I have time to switch.

My experience is that they will only last about 3 to 4 years before ultraviolet rays cause the plastic to become brittle and crack. I guess using them immersed underwater as intended shelters them from the UV that they are exposed to sitting on benches in the sun.
Or perhaps this is only a result of using them in this high desert environment where the UV exposure is responsible for some of the highest rates of skin cancer in the country.

 

[minkes]

For me colanders works really good mostly for my pines, spruces and thujas. I see the best results when they are sitting on the ground allowing some roots to escape. In my enviroment it looks like deciduous trees dont like them. Here are examples of my trees in colanders. We are quite rainy area from autumn till spring with zone like 6b according to US zones.

 

[penumbra]

My experience is that they will only last about 3 to 4 years before ultraviolet rays cause the plastic to become brittle and crack. I guess using them immersed underwater as intended shelters them from the UV that they are exposed to sitting on benches in the sun.
Or perhaps this is only a result of using them in this high desert environment where the UV exposure is responsible for some of the highest rates of skin cancer in the country.

Of coarse we need to gauge things from our own set of circumstances, but I have pond baskets that have been in use for 8 or 10 years.

 

[Attmos]

My experience is that they will only last about 3 to 4 years before ultraviolet rays cause the plastic to become brittle and crack. I guess using them immersed underwater as intended shelters them from the UV that they are exposed to sitting on benches in the sun.
Or perhaps this is only a result of using them in this high desert environment where the UV exposure is responsible for some of the highest rates of skin cancer in the country.

Water doesn't block much UV radiation, so maybe they last longer in the water because they stay hydrated and cool. Maybe it's the hot dry air combined with the intense UV exposure.

 

[NashsMan]

I have all of my developing pines and even a few deciduous trees in either pond baskets or cheap plastic colanders. I'm in Zone 7B and all of these are in full sun for about 6 hours per day. My soil mixes are at least 50% pumice, and except for the 90°+ F. days, I find that I only need to water once per day. In fact, the pines only get watered every 2 or 3 days. Everything is growing very well.
I do have cedar grow boxes for some of my larger trees (mostly deciduous at this point, but with many JBP, JRP and 2 JWP coming along well, I'm going to build 8 or 10 more grow boxes this fall for repotting season '26).