Moisture level under the trunk...and roots.

[fredman]

It might seem like i'm over thinking this, but its something to think about....I think
Up to now i've exclusive used deeper pots...commercial and plastic bonsai pots as well as other containers. This year (with the repot) i've started using some proper shallow pots, for the first time.
Looking at them...I'm actually quietly anxious thinking how i'm going to keep them properly hydrated come high summer. I'm already watering sometimes twice daily with the "deeper" pots.
Now i'm thinking....some of them (in their very shallow pots) has a proper dense root system around the base. Some of them only has a sliver of soil around the side edges. When I water (especially on those very hot days), will sufficient moisture fill the centre of the container...under the roots....?
The water certainly can't flow through the roots...as its way to dense.
What do you people do...dunk them?
Do you solely rely on the water diffusing to the underside...?

 

[leatherback]

The water certainly can't flow through the roots...as its way to dense.
What do you people do...dunk them?
Do you solely rely on the water diffusing to the underside...?

I just top-water all my trees. When I repot I do ensure open areas in the rootball exist. I do have to water two passes in 10 minutes on some more mature trees to ensure the rootball gets propaerly watered

 

[fredman]

Yeah in contemplation now I realised I haven't thought it through properly.
The water will slide down the edges of the pot...all the way to reach to the middle...under the roots.
That's why its so important to water a pot in a few passes during a watering session....especially moss covered pots.

 

[Shibui]

Some of them only has a sliver of soil around the side edges.

Older trees that have developed fused roots or very thick trunk certainly do shelter part of the pot from water. Some of my older maples have completely fused roots to form a plate of wood that covers much of the pot surface. Easy to wet the outer soil but under the root base is protected and can stay dry.
I make sure I water properly which may include several passes ate each watering - water the pot as normal. Move on to other trees then return to the start and water again. First pass wets outer soil and soaks in under the roots a little. Second pass waters outside soil again and soaks in under the root base a little further. 2-3 passes required to properly wet.

I do have to water two passes in 10 minutes on some more mature trees to ensure the rootball gets propaerly watered

Japanese growers talk about watering bonsai 3 times - for the leaves, for the trunk and for the roots. I suspect this is for the reason we are talking about - applying enough water with some time between to allow the water to soak through the entire pot.

 

[PA_Penjing]

I have some good news for you, the water actually drains from a shallow pot more slowly. It's physics that I'm tpo dumb to explain but there are some good break downs on this site if you search. "water table" "bonsai pot" they would probably come up. the water drains out of a shallow pot more slowly. At the end of the day they are probably still more likely to dry faster than a larger pot but if it puts your mind at ease it might be worth a read. Also sounds liek you could maybe use a soil component with higher capacity to hold water. it's individual prference but I have my soils at a point where I water twice on a very hot day, once on a typical warm day. But that's simply me and my climate, our climates are wildly different

 

[PA_Penjing]

Alos didn't answer your last question, dunking is porbably great but I don't do it. I water everything once, to wet the soil. Then a a few minutes later i water it deeply. I have a very green thumb and this has never let me down. Don't ask me about styling or aesthetics though...

 

[Michael P]

Japanese proverb, "For bonsai it always rains twice."

 

[PA_Penjing]

HOLY TYPOS! I'm glad I called myself dumb at least haha