Terracota pots - They dry faster

Clicio

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There is a myth around here that terracota pots (for seedlings, saplings and training plants) are way better than plastic pots.
My observation so far is:
Given pots with the same size, draining holes and volume, with the same substrate and plants inside, but plastic X terracota = terracota dries much faster.
Regardless of size (both big and small pots).
Well, terracota "breathes", but the difference seems to be bigger than I had thought; in small sapling pots, the substrate dries twice as fast as plastic.
Good if you have time to water two times a day, bad if you don't.
But is this (terracota) necessarily better?
 
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From my experience, and that's not much so take it with a grain of salt, could it be that terracotta pots are "wicking" away the moisture from the soil by soaking it up into the pores of the pot?
Also I've noticed that plastic pots heat up much more in the sun then terracotta, is that something to consider since I'm sure roots can't handle too much heat?
 

Starfox

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Hmm, my observation differs. I find terracotta soaks up the water(which may be part of the issue you are seeing) but in turn keeps the conditions damper in the substrate longer. And the non bonsai terracotta planters show this even more and require way less water than you would think. Plenty of those pretty weeds have been killed from overwatering in them. They are great in my climate for bonsai at least, thinking of getting more.
 

JoeR

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I made the switch to terra this year for many of my trees and I’ve definitely noticed the same thing. They dry considerably faster, which I didn’t know until after potting them in it. My hope is that the roots still stay happier and much cooler, although maybe drier, than they were in black plastic pots. I think the heat really gets to my trees in the summer so I’m hoping they’ll be better off still. They also look WAY better than ugly plastic pots, and they’re heavy too so trees don’t have to be tied down most of the time.
 

GGB

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can't call one better, definitively. I love terracotta because they breathe like a lung, to me the idea of trapping moisture around roots for a long time is no good. I'd rather water more and flush out old crud and pull in oxygen as opposed to watering every however many days. But it all just depend on your availability to water
 

GGB

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...and maybe species. but I'd rather have terracotta in my yard than ugly flimsy plastic
 

Clicio

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I find terracotta soaks up the water(which may be part of the issue you are seeing) but in turn keeps the conditions damper in the substrate longer.
I see. But...
Summers (and springs, and falls...) here can be very hot, perhaps this evaporation is not giving time to soil get damp long enough, which I think is good for the roots.
While with plastic, water keeps inside, trapped.
 

Clicio

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I think the heat really gets to my trees in the summer so I’m hoping they’ll be better off still

This is exactly my reasoning too. They seem to like it (terracota) better when it's hot hot.
 
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River's Edge

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can't call one better, definitively. I love terracotta because they breathe like a lung, to me the idea of trapping moisture around roots for a long time is no good. I'd rather water more and flush out old crud and pull in oxygen as opposed to watering every however many days. But it all just depend on your availability to water
I would vote for terracotta every day, all day if it were not for the freeze factor. Hate replacing cracked pots. This is another one of the it depends on your climate situations. The quality of the pot determines how often or if it cracks in freezing weather. I find the terracotta from some Italian suppliers stands up better than others I have tried.
 

Starfox

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I see. But...
Summers (and springs, and falls...) here can be very hot, perhaps this evaporation is not giving time to soil get damp long enough, which I think is good for the roots.
While with plastic, water keeps inside, trapped.

I see your point but we have long, hot and more dangerously, winds here in Spain and I have always looked at the terracotta pots as being more of a buffer against those conditions.
Maybe substrate plays a part, I use either akadama or DE as my main substrate and it would be good to know terracottas water holding abilities compared to them. I think all 3 are good at holding water, But if you water until water is coming out the drainage holes and hold it then the substrate should have enough time to soak it up first. I'm not sure it can wick it out of DE but to be fair I don't know.
The terracotta you can visibly see is holding water, so is the substrate, a stone ware or plastic pot does not hold that water so it goes straight out and therefor the substrate evaporates quicker whereas terracotta holds the water, in theory breathes and may even act to cool the pots down.

All of that said maybe I am using more water on a terracotta pot as I judge by the substrate how much water is needed. And only on rare occasions would I ever water twice a day.

It's an interesting observation and has got me thinking at least so now I'm mildly curious.
 

GGB

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Yes, @GrimLore tipped me off to the "made in Italy" stamp that appears on some. Apparently those are for us northerners. The cracking business kind of stinks but if I over winter in a garage it's not bad. And if it breaks up a little it just adds character
 

River's Edge

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I see. But...
Summers (and springs, and falls...) here can be very hot, perhaps this evaporation is not giving time to soil get damp long enough, which I think is good for the roots.
While with plastic, water keeps inside, trapped.
Roots do best in a combination of aeration,moisture and nutrient availability. Terracotta breaths and does not heat up as much as plastic pots. This means more even temperature, less extremes and better aeration. If the substrate dries out too quick, one can alter the soil components to increase the water retention capacity and/or use sphagnum moss on top to slow down evaporation. Simply increasing the percentage of Akadama, or Pine Bark, or whichever component you use for higher water retention capacity. If your conditions are very hot and windy then avoid pond baskets or colandars unless placed in the ground.
This is just an extension of the same principle of adjusting soil mixes to suit the watering needs of particular species wether it is PH or Water requirements. Perhaps review your soil component choices to ensure they have enough water retention capacity and are not too large a particle size for the purpose.
One can also adjust their watering methods. Water thoroughly, come back in a few minutes and do it again. This gives the substrate time to soak up the water. Often people choose to sit the pot in water for a few minutes to make sure that the whole rootball and media has had the opportunity take up the moisture.
Sometimes it is a simple water of incorrect watering, inconsistent watering. The pot is not the only variable and frequently not the most important variable. Hope these ideas help.
 
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