Do junipers really "drink" water through their foliage?

[Clicio]

Recently I've been to a bonsai nursery, whose owner is Japanese, specializing in conifers.
I bought a nice Kishu juniper to add to my collection, and out of curiosity asked him about the frequency of watering he was using, since our climates are very similar.
It turns out that he told me :
"I don't water the soil of junipers at all, I mist them 4 times a day. They get all the water they need through the green mass."
Well, I got to see how, and he wasn't manually misting, but using those big automated agricultural irrigation devices adjusted for a fine mist.
Well, if it rains, it rains also on the soil, he proceeded to tell me.
So I tried to find more info about not watering the soil of junipers and could find none. Yes, they are very drought resistant, yes they need the soil to dry out between waterings, but that's all.
Can anyone confirm if misting a lot is enough for junipers, or is this another unproven myth of bonsai?

 

[Paradox]

I think it's largely unproven.
I just did a quick search and found that yes trees can absorb water through their foliage (leaves, needles), but it's not efficient so debatable whether they get enough water that way.

I've been keeping junipers for 12 years and I water with an overhead sprinkler so both the soil and foliage get wet. I watered by hand for a few years before the sprinkler and the foliage didn't get wet as much.
Trees all lived in both cases

Those big agricultural misters put out a lot of water. Depending on how long each session is, its possible with that much misting that enough drips down to the soil and it gets wet anyway

 

[Dav4]

Junipers, like other plants, have stomata- essentially small openings in the leaves- that allow gaseous exchange. The thought is that the typical juniper yamadori lives in a fairly arid environment where water is scarce, but the night time air cools to the point where ambient humidity is 100% in early morning, and that moisture can move into the tree through the stomates. These openings will decrease in size as the sun rises to reduce moisture losses during the hot and dry day. It's definitely a thing, and the best treatment of collected junipers in arid environments like CA utilize that feature by essentially misting the foliage instead of watering the roots until the tree has recovered from collection by regrowing a new root system... at which point most would start watering the soil .

 

[Orion_metalhead]

Yes, they are very drought resistant, yes they need the soil to dry out between waterings, but that's all.

How dry are we talking about? My junipers which get watered daily look a lot better than my junipers which tend to dry out more.

Havent heard about this necessity.

 

[Clicio]

Those big agricultural misters put out a lot of water. Depending on how long each session is, its possible with that much misting that enough drips down to the soil and it gets wet anyway

Thanks @Paradox , I guess you are right.
If one thinks that our summers are very wet and it rains almost every day, it makes perfect sense.

 

[Joe Dupre']

My hunch is this: Nature doesn't normally just "do things" for no reason. Junipers have foliage year round because they NEED it year round. They may need it to get whatever they need , anyway they can get it. They normally come from fairly harsh environments where resources are scarce. Getting water and nutrients through needles, roots or even bark may be an evolutionary adaptation. .............. Or not.

 

[Clicio]

... arid environments like CA utilize that feature by essentially misting the foliage instead of watering the roots until the tree has recovered from collection by regrowing a new root system... at which point most would start watering the soil .

Yes @Dav4 , if one thinks stomata in junipers can keep the water inside by closing at daytime - more than other species, according to the article below - then it makes perfect sense.

https://treejourney.com/heres-how-much-water-junipers-really-need-watering-guide/

 

[Clicio]

Havent heard about this necessity.

Well, I guess it is not a necessity, but a technique.

 

[Clicio]

This is an interesting article, by the way;

"Here is how much water junipers really need"

 

[It's Kev]

i think for us in hotter climates, just make sure the water goes where it should, to the roots

 

[Paradox]

My hunch is this: Nature doesn't normally just "do things" for no reason. Junipers have foliage year round because they NEED it year round. They may need it to get whatever they need , anyway they can get it. They normally come from fairly harsh environments where resources are scarce. Getting water and nutrients through needles, roots or even bark may be an evolutionary adaptation. .............. Or not.

I've read that juniper that grow along the coast get water from the humidity, fog, mist common along the coast as well as from the roots.

Lots of juniper also spend months under feet of snow during winter so one wonders what their foliage does for them during that time.

We do know needles lose less water than leaves via transpiration which allows them to be more drought tolerant.

 

[BrianBay9]

My hunch is this: Nature doesn't normally just "do things" for no reason. Junipers have foliage year round because they NEED it year round. They may need it to get whatever they need , anyway they can get it. They normally come from fairly harsh environments where resources are scarce. Getting water and nutrients through needles, roots or even bark may be an evolutionary adaptation. .............. Or not.

Deciduous trees lose their leaves in fall in anticipation of having no available water in the winter. Frozen water is not useful. They can't photosynthesize. Conifers don't lose as much water through their needles, so they keep them.

 

[Orion_metalhead]

But does any of this translate to bonsai culture? I mean, growing a juniper in a landscape. Even in harsh environments, does not translate entirely.

 

[Clicio]

I've read that juniper that grow along the coast get water from the humidity, fog, mist common along the coast...

Ah, so have I.

 

[PaulH]

I've collected yamadori junipers with next to zero roots and with regular foliage misting they survive and grow new roots.

 

[Clicio]

I've collected yamadori junipers with next to zero roots and with regular foliage misting they survive and grow new roots.

That's very interesting, Paul.
This japanese grower tells me the same, for junipers coming from the ground, just misting for a couple of years.

 

[sorce]

Dew you believe?

Sorce

 

[It's Kev]

But does any of this translate to bonsai culture? I mean, growing a juniper in a landscape. Even in harsh environments, does not translate entirely.

Maybe for that we can go back to the reasoning how the earth isn’t like a pot and your landscape juniper is better off because of “earth magic”
I suppose it will get moisture from foliage when it can, but it doesn’t really “need” to because your yard holds moisture better than a pot because it’s bigger and doesn’t get much heat from the side (earth being enormous and all) like a pot would because the sun’s rays from the side of a pot could also contribute to moisture loss

 

[Joe Dupre']

I've always watered my junipers' soil and foliage. At the suggestion of a friend, I've started foliar feeding. So far, I see an improvement in color and health.

 

[Clicio]

I've always watered my junipers' soil and foliage. At the suggestion of a friend, I've started foliar feeding. So far, I see an improvement in color and health.

I have mixed feelings about foliar feeding, it seems that many species don't like it at all. And one has to be cautious, by not pulverizing the trees under the sun.