Japanese Maples Chill Hour Requirements

Cajunrider

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Puzzling...since Japanese maples can't be grown in south Florida. They have zone envy because of this.

Are you sure...you are a zone 11?
I have seen Japanese maples in South Florida but only in inland area away from the sea air. For me I struggled to grow JM at my old house near the sea. The salt air burned the leaves no matter what I tried. That happened not only with JM but also with many other species including Chinese chestnuts which practically grow anywhere. Once I moved further in land JM grow fine in areas where there is only morning sun.
 
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Weaponman

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The owner Joe took on a partner recently. I only saw a vast number of jade plants in water tubs the last time we were there. No maples and Joe had said they wouldn't grow there as have a number of people who've tried.
Yours is looking good. You're keeping it in a lot of shade...? Makes me want to try one. Did you buy it in Orlando? I'm in Winter Park. There are a few plant shops nearby that have bonsai but the prices are comical.
Where do you buy your trees?
Jade plants in water tubs sounds like a bad idea. Acer rubrum can take mostly sun, this one is in filtered sun, but it does love wet feet since it naturally grows in wet soils. Get a big dish or humidity tray and use finer particles of pumice and more organic matter to your bonsai mix. You won't find this at any of the bonsai places because sadly those bonsai shops all kind of suck. They sell cheap soil, cheap pots, and cheap chinese grown plants. I recommend you go to a commercial or native nursery and get a tree. This one was a yamadori sapling, but you can easily get a 3 gal nursery stock if you want to train early, or get a larger container nursery stock with a fat trunk and give it the chop, now is the right time to do it. Lowes sells them too. You can also try to collect one from a swamp forest. I've found that it is a pretty forgiving plant species. Any wetland area in your area will probably have some red maple seedlings, I saw a few near my house the other day.
If you want to check out a cool native nursery with reasonable prices, go to Green isle Gardens in Groveland. It's worth a trip. They have all kinds of unusual native species suitable for bonsai: sand pines, simpson stopper, southern crabapple, red maple, dwarf blueberries, etc.
 

Weaponman

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Jade plants in water tubs sounds like a bad idea. Acer rubrum can take mostly sun, this one is in filtered sun, but it does love wet feet since it naturally grows in wet soils. Get a big dish or humidity tray and use finer particles of pumice and more organic matter to your bonsai mix. You won't find this at any of the bonsai places because sadly those bonsai shops all kind of suck. They sell cheap soil, cheap pots, and cheap chinese grown plants. I recommend you go to a commercial or native nursery and get a tree. This one was a yamadori sapling, but you can easily get a 3 gal nursery stock if you want to train early, or get a larger container nursery stock with a fat trunk and give it the chop, now is the right time to do it. Lowes sells them too. You can also try to collect one from a swamp forest. I've found that it is a pretty forgiving plant species. Any wetland area in your area will probably have some red maple seedlings, I saw a few near my house the other day.
If you want to check out a cool native nursery with reasonable prices, go to Green isle Gardens in Groveland. It's worth a trip. They have all kinds of unusual native species suitable for bonsai: sand pines, simpson stopper, southern crabapple, red maple, dwarf blueberries, etc.
Also check out Green's nursery in Sorrento. They have a lot of old neglected stock so you might have to hunt through it but they have some good stock as well. Dwarf schefflera, boxwoods, weeping yaupon hollies, chickasaw plums, simpson stopper. Even a few japanese maples.....
 

Katie0317

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Also check out Green's nursery in Sorrento. They have a lot of old neglected stock so you might have to hunt through it but they have some good stock as well. Dwarf schefflera, boxwoods, weeping yaupon hollies, chickasaw plums, simpson stopper. Even a few japanese maples.....
Thanks for sharing those. I've been to Greens Nursery and found a treasure there. An abandoned rose that was really special.

Have you not been to D&L nursery in Oklawaha? You won't find a better source for both pre-bonsai and finished bonsai trees. The owner is my teacher and he became a friend. Eventually David Cutchin (who works there full time) will be the sole owner. D Cutchin teaches for Mirai and he and Ryan and good friends.

They have workshops on a lot of weekends so you should get their newsletter before you go. You wouldn't want to go during a workshop because there would be no one to answer questions and help you etc.. Awesome, magical place. David VanBuskirk is the owner. It's not a landscape nursery, but a bonsai nursery and they grow everything they sell. No imports. They don't sell anything via mail.
 

Weaponman

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Thanks for sharing those. I've been to Greens Nursery and found a treasure there. An abandoned rose that was really special.

Have you not been to D&L nursery in Oklawaha? You won't find a better source for both pre-bonsai and finished bonsai trees. The owner is my teacher and he became a friend. Eventually David Cutchin (who works there full time) will be the sole owner. D Cutchin teaches for Mirai and he and Ryan and good friends.

They have workshops on a lot of weekends so you should get their newsletter before you go. You wouldn't want to go during a workshop because there would be no one to answer questions and help you etc.. Awesome, magical place. David VanBuskirk is the owner. It's not a landscape nursery, but a bonsai nursery and they grow everything they sell. No imports. They don't sell anything via mail.
Kind of far for me. But thanks for the tip.
There’s another nursery called the natives, which is in Davenport. They have a lot of interesting native species and I’m pretty sure there’s some guys that work there that mess around with bonsai.
 
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Puzzling...since Japanese maples can't be grown in south Florida. They have zone envy because of this.

Are you sure...you are a zone 11?
Historic records show that minimum temperature ever recorded at sea level is 6 Celsius. I’m at about 50 m above sea level. I have since found a few places around the island where Japanese maples are grown in gardens. Mine is still going strong, despite the fact that the pot fell and broke half of th tree 😌
I just got a deshojo and a Katsura. Still just stocks in a pot but let’s see what they can handle.
 

Cadillactaste

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Historic records show that minimum temperature ever recorded at sea level is 6 Celsius. I’m at about 50 m above sea level. I have since found a few places around the island where Japanese maples are grown in gardens. Mine is still going strong, despite the fact that the pot fell and broke half of th tree 😌
I just got a deshojo and a Katsura. Still just stocks in a pot but let’s see what they can handle.
Yeah...that puts you at a zone 11. I guess...it depends on climate as well. As to a depends factor. As my friends are so envious of our northern Japanese maple bonsai. It just made me pause. But ... trees don't read books. 😉 they do their thing.
 

Katie0317

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Kind of far for me. But thanks for the tip.
There’s another nursery called the natives, which is in Davenport. They have a lot of interesting native species and I’m pretty sure there’s some guys that work there that mess around with bonsai.
The natives is really interesting. They have a lot of trees used for bonsai. Fascinating work they're doing. We're both Fl natives and hate to see what's happened to out natural resources.
You must be on the west side of central Florida. It's a sprawl here!
 

Weaponman

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Southwest Orange County. Florida grows houses now.
 

cloudforest

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Interested if there's new data from this thread.
 

andrewiles

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I'll add one tidbit. As an experiment this summer I took some 2 year old vine, red and palmatum maples, which had already formed buds, and forced them into dormancy by placing them in a beverage cooler set at 35F. I kept them there for 2 months. I recently took them out and placed them under grow lights. After about a week all were opening buds as they would in the spring. Seem healthy so far. Worked for a gingko and hawthorn as well.

So, while it's just one unscientific datapoint, it would seem that 1300 chill units at ~35F is plenty for maples in general. Based on how fast bud break occurred I suspect fewer chill units are very doable.

I'm a bit surprised the zone 10+ crowd here hasn't been doing this with some nicer trees. An old fridge is pretty cheap and could hold a few trees. Trees in for just two months in the winter to ensure proper dormancy, then back out on the benches.

One thing I learned is that you can't completely forget them -- have to water every few weeks so they don't dry out.
 

cloudforest

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I'll add one tidbit. As an experiment this summer I took some 2 year old vine, red and palmatum maples, which had already formed buds, and forced them into dormancy by placing them in a beverage cooler set at 35F. I kept them there for 2 months. I recently took them out and placed them under grow lights. After about a week all were opening buds as they would in the spring. Seem healthy so far. Worked for a gingko and hawthorn as well.

So, while it's just one unscientific datapoint, it would seem that 1300 chill units at ~35F is plenty for maples in general. Based on how fast bud break occurred I suspect fewer chill units are very doable.

I'm a bit surprised the zone 10+ crowd here hasn't been doing this with some nicer trees. An old fridge is pretty cheap and could hold a few trees. Trees in for just two months in the winter to ensure proper dormancy, then back out on the benches.

One thing I learned is that you can't completely forget them -- have to water every few weeks so they don't dry out.
They need even less than that. In my climate, it doesn't get below 50F in the Winter. But we have lots of hours between 50F and 65F. My JM leaf out in June. Note that our seasons in Hawaii are 2.5 months behind the solstices. So peak cold is March and April, peak heat is Sept -Oct. Trident maple needs even less. June is still cool, 68-72F. I have been talking to folks in Thailand about acer, seems burgerianum, rubrum, platanoides and saccharinum all just molt in late Spring, don't even need dormancy in Bangkok.
 

Clicio

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I'll add one tidbit. As an experiment this summer I took some 2 year old vine, red and palmatum maples, which had already formed buds, and forced them into dormancy by placing them in a beverage cooler set at 35F. I kept them there for 2 months. I recently took them out and placed them under grow lights. After about a week all were opening buds as they would in the spring. Seem healthy so far. Worked for a gingko and hawthorn as well.

So, while it's just one unscientific datapoint, it would seem that 1300 chill units at ~35F is plenty for maples in general. Based on how fast bud break occurred I suspect fewer chill units are very doable.

I'm a bit surprised the zone 10+ crowd here hasn't been doing this with some nicer trees. An old fridge is pretty cheap and could hold a few trees. Trees in for just two months in the winter to ensure proper dormancy, then back out on the benches.

One thing I learned is that you can't completely forget them -- have to water every few weeks so they don't dry out.
Interesting.
How did you deal with mold?
Any lights needed, or completely dark environment?
 

Weaponman

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They need even less than that. In my climate, it doesn't get below 50F in the Winter. But we have lots of hours between 50F and 65F. My JM leaf out in June. Note that our seasons in Hawaii are 2.5 months behind the solstices. So peak cold is March and April, peak heat is Sept -Oct. Trident maple needs even less. June is still cool, 68-72F. I have been talking to folks in Thailand about acer, seems burgerianum, rubrum, platanoides and saccharinum all just molt in late Spring, don't even need dormancy in Bangkok.
I recently went to a nursery near Stuart in south FL, with is zone 10, and the owner had a decent looking JM. He just keeps it in an airy spot that get plenty of shade. No specific cultivar.

I have a few that I’m playing with but they seem ok as long as they are in full shade and don’t overheat. Long term, we shall see.
 

andrewiles

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Interesting.
How did you deal with mold?
Any lights needed, or completely dark environment?
I've only tried this on one set of saplings, so not a lot of data. But I didn't have mold issues. I did spray them with a fungicide before they went in, and I kept them fairly dry. The humidity stayed around 45%. I kept an open cup of water in the cooler as well -- may have helped with the humidity.

The cooler has a glass door on the front, so some light gets in during the day, but it would be very dim. It's in the garage. Since everything in there is dormant I don't think any light is needed.

Here's the cooler:
PXL_20231006_131300989.jpg

I took this second year Happy Corallinum cutting out on August 24 after around 8 weeks in dormancy. I had given it an early start in late winter. Now under some grow lights in my garage, so the leaves are pretty dark. No indication of problems from such a short dormancy, and the off-season wake-up. Time will tell.
PXL_20231006_131440696.jpg

Mainly trying this so I can have some things to play with during the winter.
 
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I'm a bit surprised the zone 10+ crowd here hasn't been doing this with some nicer trees. An old fridge is pretty cheap and could hold a few trees. Trees in for just two months in the winter to ensure proper dormancy, then back out on the benches.
Because there is no need to bother. I’ve been happily growing JM for at least 6-7 years now in zone 11 with no problems. I just leave them outside with all the other trees (tropicals included). They do fine. They need protection (read that as shade) from late spring, through summer. But no worries about winters. They tend to drop leaves later as expected but they still do the regular cycle.
 

cloudforest

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Because there is no need to bother. I’ve been happily growing JM for at least 6-7 years now in zone 11 with no problems. I just leave them outside with all the other trees (tropicals included). They do fine. They need protection (read that as shade) from late spring, through summer. But no worries about winters. They tend to drop leaves later as expected but they still do the regular cycle.
You're in the Azores? What are your Winter temps like? There's still plenty of chill accumulation between 7.5C and 10C and your temps rise to no more than maybe 20C in the Winter. That's way different from a Florida zone 10 where it drops into the 0-5C range once or twice per Winter and then it is back to 18C night to 27-30C days. Winter heat will cancel our most chill. Here in the mountains in Hawaii in a zone 11b/12a the Japanese maples leaf out in July and lose their leaves in December-January.
 

Clicio

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Because there is no need to bother. I’ve been happily growing JM for at least 6-7 years now in zone 11 with no problems. I just leave them outside with all the other trees (tropicals included). They do fine. They need protection (read that as shade) from late spring, through summer. But no worries about winters. They tend to drop leaves later as expected but they still do the regular cycle.

Yes.
I've been growing maples for years in zone 11a and guess what?
They are thriving.
 
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