Acer palmatum in "hot" weather ?

[clem]

Thanks for the encouragement!
These are my palmatums ( in summer, when they had leafs),as you can see they looked healthy, I hope they keep this look for so many years.This winter-spring I'll repot and turn them into bonsai.

Both seem very healthy, and don't seem to lack of watering or fertilisation/micro-nutriments. I used to cultivate a yama-momiji of my best friend a year ago, for just 1 year but i can tell you it is very strong if it is happy in it's location and cultivation

 

[Jan JC]

What is your relative humidity like in the summer? A hot AND dry wind during the summer months will definitely damage A. palmatum leaves. Without knowing anything else about your microclimate, I suspect you'll need both sun and wind protection and if truly dry with low humidity, misting during the day will be very helpful

Humidity during all the year is quite high, due to the proximity to the sea.
It's usually between 60-70% during day and during night raises till 90% or even 100%.
There are minimal variations between seasons, but not further than +-5% .
Despite this , some days northern wind can blow and humidity falls to less than 35%, but then raises again, so no problem.

 

[Shibui]

Our winters are just a bit cooler than yours in Barcelona. In winter temps dip just below freezing many nights but winter day temps are usually 10-20C. Summer here is much warmer. 40C is expected and 43C a couple of days each summer.
Japanese maple do fine here but do need some shade in summer and plenty of water. They also grow well further north in even warmer winters so I expect yours will do OK. They don't really like the sub-tropics where winter temps rarely go below 10C at night but people persist in trying to grow them.
Your humidity will have some advantage in warmer weather. Here on the hottest days humidity can be down to 10% RH which really challenges JM leaves
I have found that Seryu is a very hardy variety so I am not surprised that yours has done well.

Keep working with your Japanese maples. I think they should grow OK there. Be aware that keeping them alive is not the hardest part. JM have special requirements for pruning and maintenance that make keeping them looking good as bonsai in the long term more difficult. Trident maple will give you everything that JM has (except the name Japanese) but are far easier to manage, much quicker to develop as bonsai and tolerate a wider temp range.

 

[Jan JC]

Our winters are just a bit cooler than yours in Barcelona. In winter temps dip just below freezing many nights but winter day temps are usually 10-20C. Summer here is much warmer. 40C is expected and 43C a couple of days each summer.
Japanese maple do fine here but do need some shade in summer and plenty of water. They also grow well further north in even warmer winters so I expect yours will do OK. They don't really like the sub-tropics where winter temps rarely go below 10C at night but people persist in trying to grow them.
Your humidity will have some advantage in warmer weather. Here on the hottest days humidity can be down to 10% RH which really challenges JM leaves
I have found that Seryu is a very hardy variety so I am not surprised that yours has done well.

Keep working with your Japanese maples. I think they should grow OK there. Be aware that keeping them alive is not the hardest part. JM have special requirements for pruning and maintenance that make keeping them looking good as bonsai in the long term more difficult. Trident maple will give you everything that JM has (except the name Japanese) but are far easier to manage, much quicker to develop as bonsai and tolerate a wider temp range.

Thanks for all the info!
Now I see JM can withstand much more heat and dry weather than I expected.

About what you say about Trident Maple, Acer burguerianum, I also heard it's much more hardy than palmatum, but I've never found any here .
It's very strange to see maples in plant nurseries here, and even stranger to see other ones than palmatums ... If I ever see one, I'll buy it.

 

[Starfox]

Hola, sorry I'm not much use with JM care as such but the best places I have found for locating JM's and Tridents have been from actual Bonsai places.
I know there are more stores than this available but the 2 places I have personally ordered from and will happily do so again are Laos Garden in Madrid and Bonsai Granada. They ship anywhere and have always been quick, reliable and no fuss and I find their prices reasonable although you will pay a little more than you would in a nursery.

Both shops are light on cheap Tridents at the moment but keep an eye out as they do update stock often.
Both do have numerous JM's under 100euro, even a bunch of cheap Acer campestre available.

It would still be worth checking other stores out though, it's just I can vouch for those two personally.

 

[AlainK]

Warm, dry winds are the worst enemies of Japanese maples.

In their natural habitat, A. palmatum, amoenum, japonicum, shirasawanum, etc. are under-storey species that need no more than two or three hours of direct sun in the morning. So as long as you keep them mostly in the shade and protected from the wind, and if there's a high humidity in the air, they will thrive.

They do need a period of dormancy, but it doesn't have to be periods of frost.

And if you want Acer buergerianum seedlings, as long as Catalunia is in Europe I can send you one, for free, just PM me if you want

 

[Jan JC]

Warm, dry winds are the worst enemies of Japanese maples.

In their natural habitat, A. palmatum, amoenum, japonicum, shirasawanum, etc. are under-storey species that need no more than two or three hours of direct sun in the morning. So as long as you keep them mostly in the shade and protected from the wind, and if there's a high humidity in the air, they will thrive.

They do need a period of dormancy, but it doesn't have to be periods of frost.

And if you want Acer buergerianum seedlings, as long as Catalunia is in Europe I can send you one, for free, just PM me if you want

My Maples meet all the requirements you say (sunlight, humidity... ) so they'll be nice I'll keep you aware of how are they over the years, as well as the bonsai transformation....that I still don't know how to do....
thanks!
Oh, and about sending me those burguerianum seeds, thank you but don't worry, I'll just search around here, maybe in Barcelona's botanical garden there's some of them... anyway, I'm fine with my palmatums and saccharinum maples

 

[AlainK]

saccharinum maples

Hmmm. Big leaves, and a natural range where they support deep frosts...

There are many here planted as street trees. They are fast growers. But more and more they are replaced with other species that are more adapted to a milder climate.

 

[Jan JC]

Hmmm. Big leaves, and a natural range where they support deep frosts...

There are many here planted as street trees. They are fast growers. But more and more they are replaced with other species that are more adapted to a milder climate

Is true that they prefer climates much colder than mine, but Acer saccharinum is also used here in some streets and they grow well, so it looks like it can live quite well in my climate.
I don't have it as bonsai, just as "normal" plant, it's 3 years old.

 

[AlainK]

I often suggest people in the south of Europe to try Acer monspessulanum, or even Aver campestre. Both are more difficult to shape than Acer palmatum, but they're more suitable to a Mediterranean climate.

 

[Jan JC]

I often suggest people in the south of Europe to try Acer monspessulanum, or even Aver campestre. Both are more difficult to shape than Acer palmatum, but they're more suitable to a Mediterranean climate.

Yes, but their look isn't as elegant and beautiful...

 

[Gustavo Martins]

I often suggest people in the south of Europe to try Acer monspessulanum, or even Aver campestre. Both are more difficult to shape than Acer palmatum, but they're more suitable to a Mediterranean climate.

I've been trying to find A. monspessulanum but it's not been easy. I sourced some seeds from A. monspessulanum last year but they all failed to germinate....

Anyways I do have A. palmatum and A. burgerianum here in the Azores. They both have done good so far. In fact, I have had more problems with trident due to fungus whist the palmatum has always been super healthy. High humidity, very mild summer and winters. Winter temps only dip below 10C for maybe a week or two. summer temps rarely exceed 28C.
this year, temperature dropped a bit earlier than usual and I had beautiful fall colour for the first time, but especially on the trident. Usually, I get very little fall colour although they do shed their leaves

 

[AlainK]

Yes, but their look isn't as elegant and beautiful...

You've got a point.

But it's an exciting challenge (un défi passionant) to make a "good" bonsaï with these. There's one I've been working on for years.One of the best photos, October 15, and what it looked like in November 2020 :

 

[Jan JC]

You've got a point.

But it's an exciting challenge (un défi passionant) to make a "good" bonsaï with these. There's one I've been working on for years.One of the best photos, October 15, and what it looked like in November 2020 :

View attachment 350364 View attachment 350363 View attachment 350362

Wow !!!
Is that yours!? It's BEAUTIFUL!

 

[Gustavo Martins]

I actually disagree. I find the leaves of the A. monspessulanum quite beautiful.

 

[Jan JC]

I actually disagree. I find the leaves of the A. monspessulanum quite beautiful.

Both Acer campestris and monspessulanum are beautiful trees (all maples are, in my opinion), but compared to palmatums (which have the most beautiful leafs on any plant) they aren't as nice.

 

[AlainK]

Is that yours!?

Yes.
Like most of my trees, I'd like to sell it, but the price of shipping, even in Europe, prohibits it. So I guess I'll have to look after it for a couple more years...

EDIT : actually, one of my sons lives in Vernet-les-Bains. When I can go and visit him, I'll send you a note, it's just across the border

 

[Jan JC]

Like most of my trees, I'd like to sell it, but the price of shipping, even in Europe, prohibits it.

Isn't there any bonsai nursery or exhibition to try to sell them near you?
That tree is really nice looking, so I think you wouldn't have any problem with selling it (well, I don't know much about bonsai sales and pricing)

 

[Jan JC]

Actually, one of my sons lives in Vernet-les-Bains. When I can go and visit him, I'll send you a note, it's just across the border

Oh yes, in Catalan Pyrenees ( I went to Conflent region some time ago...before covid19..when travelling was allowed)

 

[leatherback]

How are you faring with salinity? I assume Barcelona might have some salt in the air?