Growing a coconut in a greenhouse in a temperate climate

[Motlife]

Hi all. I have an idea at some stage in the future to build a conservatory/sunroom area, which obviously would need to be filled with tropical plants! Having a coconut growing in a raised bed would be a pretty amazing sight. I'd prefer to not have to use any heating, or only something for the coldest nights. 

Here in winter night temperatures get down to about freezing fairly regularly, but never much below. I have a small unheated greenhouse now, and the minimum temp it will see is about 3c. It might have an average low of 6C over winter. But we have fairly sunny days much of the time, and it will easily get up to mid 20s to 30ishC (80sF?) on sunny days, which probably average 4 days out of 5, under glass. Outside day temps are usually between 12 and 16 mid winter. 

Has anyone ever tried to grow a coconut in similar conditions, like maybe a desert with high diurnal fluctuations? Does the warmth during the day cancel out the cool night temperatures? Or would it require a proper heated greenhouse? If it wouldn't mind the sunny days, would periods of cool temperatures for a few days during rainy and cloudy times be worse? It would usually stay around 10C during those periods, but obviously not warm up a lot during the day without sun. 

Thanks for your thoughts! 

[Than]

3 hours ago, Motlife said:

Hi all. I have an idea at some stage in the future to build a conservatory/sunroom area, which obviously would need to be filled with tropical plants! Having a coconut growing in a raised bed would be a pretty amazing sight. I'd prefer to not have to use any heating, or only something for the coldest nights. 

Here in winter night temperatures get down to about freezing fairly regularly, but never much below. I have a small unheated greenhouse now, and the minimum temp it will see is about 3c. It might have an average low of 6C over winter. But we have fairly sunny days much of the time, and it will easily get up to mid 20s to 30ishC (80sF?) on sunny days, which probably average 4 days out of 5, under glass. Outside day temps are usually between 12 and 16 mid winter. 

Has anyone ever tried to grow a coconut in similar conditions, like maybe a desert with high diurnal fluctuations? Does the warmth during the day cancel out the cool night temperatures? Or would it require a proper heated greenhouse? If it wouldn't mind the sunny days, would periods of cool temperatures for a few days during rainy and cloudy times be worse? It would usually stay around 10C during those periods, but obviously not warm up a lot during the day without sun. 

Thanks for your thoughts! 

I've never tried but coconut trees in north India withstand down to 4-5 C regularly. I guess you must choose a hardy variety. Yet, somehow, my gut feeling is not optimistic, sorry.

[RichardHemsley]

With a commercial grown coconut, the type you see in DIY stores, you would have zero chance in my opinion. They have very little cold tolerance. 

You best chance would be with one you germinate and grow yourself,  even then it sounds like your temperatures will be too cold.

[Motlife]

1 hour ago, RichardHemsley said:

With a commercial grown coconut, the type you see in DIY stores, you would have zero chance in my opinion. They have very little cold tolerance. 

You best chance would be with one you germinate and grow yourself,  even then it sounds like your temperatures will be too cold.

We don't have those Dutch ones available in nz anyway. There's only one local site that has seedlings, but I'm not sure what variety. At a guess it might be whatever is most common in places like Samoa and Tonga since theyre quite close, but no idea really. 

It would definitely be a huge zone push for sure. And if it did grow it would probably fill up the space within a decade and need to be chopped down. But it would be very cool for a while if I could get it to survive! 

[Motlife]

3 hours ago, Than said:

I've never tried but coconut trees in north India withstand down to 4-5 C regularly. I guess you must choose a hardy variety. Yet, somehow, my gut feeling is not optimistic, sorry.

I wonder if it's possible to find those varieties somehow. I imagine the ones we can get are pacific varieties. They grow in places like Pitcairn and easter Island which aren't tremendously warm during winter. But they'd also never see temps under 10 or 12. My greenhouse daytime temps would be higher than the 20c or so they getin winter, but obviously the lows are much lower. A northern Indian cultivar definitely sounds more suitable. 

 

I wonder if there are desert type areas where the climate might go from 5c in the morning to 25c most winter days that manage coconuts? Higher altitude places in Mexico maybe? 

[Than]

5 minutes ago, Motlife said:

We don't have those Dutch ones available in nz anyway. There's only one local site that has seedlings, but I'm not sure what variety. At a guess it might be whatever is most common in places like Samoa and Tonga since theyre quite close, but no idea really. 

It would definitely be a huge zone push for sure. And if it did grow it would probably fill up the space within a decade and need to be chopped down. But it would be very cool for a while if I could get it to survive! 

My uneducated guess is that Polynesian cocos are same as those in SE Asia, which are supposedly among the least hardy ones

[Motlife]

Just now, Than said:

My uneducated guess is that Polynesian cocos are same as those in SE Asia, which are supposedly among the least hardy ones

Sounds like a reasonable guess! 

[PalmsInBaltimore]

1 hour ago, Motlife said:

I wonder if there are desert type areas where the climate might go from 5c in the morning to 25c most winter days that manage coconuts? Higher altitude places in Mexico maybe? 

Coconuts do not grow in such climates. Coconuts need sun, heat, and water in high amounts. All three. Desert is too dry, and it is rare to find coconuts high above sea level. 

I think your greenhouse idea is awesome, but for coconuts it probably will need to be heated in winter. If apple trees grow well where you're from, coconuts will struggle....

This thread from San Diego is interesting. Great inspiration for greenhouse ideas, but I have a feeling the climate is significantly warmer than yours:

 

[PalmatierMeg]

Coconuts are extremely tropical. They demand full sun, high heat (25-30+C), warm nights. Also, they are not only cold sensitive (regular drops to near/at freezing will doom them) but they are also cool sensitive. Cool/chilly temps (below 20C) are lethal to them over time. Cold rain is also lethal. Coconuts cannot photosynthesize below 10C no matter how much sun they get. Cold soil can kill them and given frequent drops to freezing and cool winter temps your soil won't warm until spring.

If you are able to provide supplemental heat (at least 30C during the day, >20C at night) to your greenhouse your coconut may be able to eke out an existence but you must be diligent in caring for it. Don't worry about it growing so large you have to cut it down - it'll be lucky to survive at all. It won't flower or set seeds in your cool maritime climate nor will it do so at elevations over 1,000' altitude.

In any case, go for it and keep us updated on your results. You will add to our body of knowledge about palm growing.

[SeanK]

@PalmatierMeg is correct.

Cocos, Cyrtostachys, Latania; palms that start to shut down with an extended cool period. Not just the air - also the soil, where their feet are.

[Tyrone]

If you could get the greenhouse temps up to 20C every day in winter then yes your coconut could survive. But if you get a few 10C days as well in there expect it to die quickly. At least 20C every day is what a coconut needs. 

[Jonathan]

It's interesting how coconuts have hijacked everyone's imagination...it's like a mass hallucination of what the hive mind of palm talkers considers to be the tropical ideal! 

Obviously taste is completely subjective but personally I'm pretty ambivalent about them, there are many other palms I'd plant first if my climate was warmer, and there are so many fantastic species that will grow happily in cool  climates like ours...a Howea is a better looking facsimile of a coconut. There, I've said it and now I'm going to climb into my bunker and wait for the bombs to fall!

[Jonathan]

Having said all that, there's a guy in Canada or Alaska or somewhere seriously cold like that who's growing citrus in a greenhouse. I think he's got it dug into the ground and relies on passive heating of huge thermal mass and maybe hydronic reticulation in the soil? Can't quite remember the details.

I think it could be done if you designed it carefully and would be a fun project. You could plant the understory with smaller tropical species and when the coconut is removed you still have a cool space to enjoy. But in the meantime plant Howeas!

[SouthernCATropicals]

I think the coconut growing too tall too fast is a real issue, I planned on keeping my greenhouse for atleast 2 years but I’ve only have it since Christmas and the 10 month old coconut is shooting out the top. 


The greenhouse peaks at 6ft10inches, crazy it was just a shell 10 months ago in October

Some things I learned about greenhouses that maybe are obvious to you guys but weren’t to me. 
 

1. They don’t retain heat at all at night, they almost instantly drop to normal outside temps. 
2. Any day in the 70sf or above is way too hot for the greenhouse to be fully shut and it is really hard watching for this that they don’t burn alive. I have even close the door during the day since January so it useless outside of cloudy days and the coldest winter days 

 

I think there’s some wiggle room in terms of temperature tolerance, none of my 7 coconuts has shown winter leaf damage and one is in fully shade 1/2 the year. I saw 41f and 42f but otherwise 50f was typical mid winter temp. 

 

[Tyrone]

2 hours ago, SouthernCATropicals said:

I think the coconut growing too tall too fast is a real issue, I planned on keeping my greenhouse for atleast 2 years but I’ve only have it since Christmas and the 10 month old coconut is shooting out the top. 


The greenhouse peaks at 6ft10inches, crazy it was just a shell 10 months ago in October

Some things I learned about greenhouses that maybe are obvious to you guys but weren’t to me. 
 

1. They don’t retain heat at all at night, they almost instantly drop to normal outside temps. 
2. Any day in the 70sf or above is way too hot for the greenhouse to be fully shut and it is really hard watching for this that they don’t burn alive. I have even close the door during the day since January so it useless outside of cloudy days and the coldest winter days 

 

I think there’s some wiggle room in terms of temperature tolerance, none of my 7 coconuts has shown winter leaf damage and one is in fully shade 1/2 the year. I saw 41f and 42f but otherwise 50f was typical mid winter temp. 

 

Coconuts are big palms and you need an enormous enclosure to hold one for say 10 years.
 

Small tunnel houses heat up quickly and cool down quickly due to less thermal mass and a smaller volume of air. Thermal mass is what will hold temps higher at night and you need rocks, soil, water and lots of space to do that. Also for more even temperature distribution you need a high roof. Even when you have all of that you need some automatic system to open vents in the roof to stop the temps getting to Dubai summer heat and cooking everything. I was watching a show about Kew’s palm house and that’s a massive structure (though not as big as the Eden Project) and they have a guy who watches the temp and flicks the switch to open the upper vents at 25C. 

[ZPalms]

green malayan dwarf does ok in cooler night temps but warmer daytime, full sun is the biggest thing, cold roots would be an absolute not.

potted coconut with a decent sized greenhouse could get you far espcially if you can retain heat at least 60F or so, I intend on trying again when my greenhouse gets built and see how it responds to winter cool temperatures with passive heat in the greenhouse but allowing it full 8 hours of sun with a backup space heater just so it has enough to get it through the night.

My greenhouse will be 16x16 so it will have decent room to grow for a decent amount of time.

[PalmatierMeg]

13 hours ago, Jonathan said:

It's interesting how coconuts have hijacked everyone's imagination...it's like a mass hallucination of what the hive mind of palm talkers considers to be the tropical ideal! 

Obviously taste is completely subjective but personally I'm pretty ambivalent about them, there are many other palms I'd plant first if my climate was warmer, and there are so many fantastic species that will grow happily in cool  climates like ours...a Howea is a better looking facsimile of a coconut. There, I've said it and now I'm going to climb into my bunker and wait for the bombs to fall!

Totally wacky, I agree. What I don’t understand is after so many years of knowledge people refuse to get it  if you want to grow coconuts move to the tropics or warm subtropics. They will not bend to your desire to commercially grow coconut groves in Kentucky.

I have no right to criticsize as my “impossible dream” palm is Lepidorrhachis mooreana and I have no hope of ever growing one of those even if I could find one.  On the other hand I’ve contented myself with growing this species vicariously. Coconuts are plentiful and cheap, so tormenting and killing them ecologically is easily rectified by replacing them with more fodder. Anyway, have at it.

Years ago, I believed that if I cared enough, worked hard enough, studied hard enough and experimented I would be successful growing palms that common knowledge said I could not (Brahea, Rhopalostylis, Hedyscepe, Jubaea etc). Uh, no, I can’t.

[Harry’s Palms]

I am one of the few palm nuts that really has no ambition to grow Coconut palms . I like most palms and after visiting tropical places , like Tahiti and Hawaii , I just don’t get it. They look great in the right place , not in my collection. I do miss my greenhouse at my old residence that allowed me to zone cheat various tropical palms but , with a ten foot ceiling , I stuck with slower growing varieties. I did worry that one day even these would out grow the environment . In the winter months I had a heater that I had from my sailboat that would keep things warm , in the summer I would open the upper gable windows and allow the prevailing wind to circulate . It was an ideal environment for palms and orchids . A coconut would’ve taken too much space . Harry

[PalmatierMeg]

Bottom line, most people would rather bask in their perfect temperate or mediterranean climates composting dead coconuts than move to a more suitable climate to grow them. I get it although sometimes the snarkiness toward us that made the move gets a bit tiresome. The Florida climate is brutal 6-7 months of the year, esp. to older people. Some people have such delicate constitutions that a 50% humidity, 80+F day sends them crashing in flames (just ask my late Aunt Frances from San Jose, CA - oh, wait).

 

[SeanK]

15 hours ago, Tyrone said:

Coconuts are big palms and you need an enormous enclosure to hold one for say 10 years.
 

Small tunnel houses heat up quickly and cool down quickly due to less thermal mass and a smaller volume of air. Thermal mass is what will hold temps higher at night and you need rocks, soil, water and lots of space to do that. Also for more even temperature distribution you need a high roof. Even when you have all of that you need some automatic system to open vents in the roof to stop the temps getting to Dubai summer heat and cooking everything. I was watching a show about Kew’s palm house and that’s a massive structure (though not as big as the Eden Project) and they have a guy who watches the temp and flicks the switch to open the upper vents at 25C. 

If I were to grow a tropical palm in a home conservatory, it wouldn't be a coconut. Too tall, too fast. Maybe Cyrtostachys or Licuala. Start supplemental heat at 50°F.

[Motlife]

Wow, even if the idea is a bit mad it definitely seems it has crossed other peoples minds too! The reason I even considered it was how well some fairly tropical things have been doing this winter in my wee unheated greenhouse. Frangipani has kept growing without dropping leaves and going dormant and papaya has been doing well too. But I know that a coconut is more sensitive than those species. But who knows, I have a mango tree growing outside happy as, so far, this winter, and I never thought that would be a possibility. It doesn't have protection apart from good siting.

On 8/16/2024 at 11:22 PM, PalmsInBaltimore said:

Coconuts do not grow in such climates. Coconuts need sun, heat, and water in high amounts. All three. Desert is too dry, and it is rare to find coconuts high above sea level. 

I think your greenhouse idea is awesome, but for coconuts it probably will need to be heated in winter. If apple trees grow well where you're from, coconuts will struggle....

This thread from San Diego is interesting. Great inspiration for greenhouse ideas, but I have a feeling the climate is significantly warmer than yours:

 

 

On 8/17/2024 at 10:06 AM, Tyrone said:

If you could get the greenhouse temps up to 20C every day in winter then yes your coconut could survive. But if you get a few 10C days as well in there expect it to die quickly. At least 20C every day is what a coconut needs. 

I wonder. 2 days ago we had a cloudy day with rain in the avo, greenhouse got up to 16. So it would likely be a struggle

On 8/17/2024 at 10:26 AM, Jonathan said:

Having said all that, there's a guy in Canada or Alaska or somewhere seriously cold like that who's growing citrus in a greenhouse. I think he's got it dug into the ground and relies on passive heating of huge thermal mass and maybe hydronic reticulation in the soil? Can't quite remember the details.

I think it could be done if you designed it carefully and would be a fun project. You could plant the understory with smaller tropical species and when the coconut is removed you still have a cool space to enjoy. But in the meantime plant Howeas!

Don't worry, I have about 40 species so far that should do well here, including a few kentias and one belmoreana. But coming home in winter to a warm conservatory with a coconut or similar tropical things growing sounds pretty good!

On 8/17/2024 at 11:46 AM, SouthernCATropicals said:

I think the coconut growing too tall too fast is a real issue, I planned on keeping my greenhouse for atleast 2 years but I’ve only have it since Christmas and the 10 month old coconut is shooting out the top. 


The greenhouse peaks at 6ft10inches, crazy it was just a shell 10 months ago in October

Some things I learned about greenhouses that maybe are obvious to you guys but weren’t to me. 
 

1. They don’t retain heat at all at night, they almost instantly drop to normal outside temps. 
2. Any day in the 70sf or above is way too hot for the greenhouse to be fully shut and it is really hard watching for this that they don’t burn alive. I have even close the door during the day since January so it useless outside of cloudy days and the coldest winter days 

 

I think there’s some wiggle room in terms of temperature tolerance, none of my 7 coconuts has shown winter leaf damage and one is in fully shade 1/2 the year. I saw 41f and 42f but otherwise 50f was typical mid winter temp. 

 

Awesome to see them doing so well! You're not so so different in climate to me, but definitely a far bit warmer in winter. My climate would be very similar to parts of the bay area, so would definitely need a lot more protection to make it work. But super cool to see how your project does!

On 8/17/2024 at 2:59 PM, ZPalms said:

green malayan dwarf does ok in cooler night temps but warmer daytime, full sun is the biggest thing, cold roots would be an absolute not.

potted coconut with a decent sized greenhouse could get you far espcially if you can retain heat at least 60F or so, I intend on trying again when my greenhouse gets built and see how it responds to winter cool temperatures with passive heat in the greenhouse but allowing it full 8 hours of sun with a backup space heater just so it has enough to get it through the night.

My greenhouse will be 16x16 so it will have decent room to grow for a decent amount of time.

Nice, I look forward to seeing how you do with it!

On 8/18/2024 at 12:32 AM, PalmatierMeg said:

Totally wacky, I agree. What I don’t understand is after so many years of knowledge people refuse to get it  if you want to grow coconuts move to the tropics or warm subtropics. They will not bend to your desire to commercially grow coconut groves in Kentucky.

I have no right to criticsize as my “impossible dream” palm is Lepidorrhachis mooreana and I have no hope of ever growing one of those even if I could find one.  On the other hand I’ve contented myself with growing this species vicariously. Coconuts are plentiful and cheap, so tormenting and killing them ecologically is easily rectified by replacing them with more fodder. Anyway, have at it.

Years ago, I believed that if I cared enough, worked hard enough, studied hard enough and experimented I would be successful growing palms that common knowledge said I could not (Brahea, Rhopalostylis, Hedyscepe, Jubaea etc). Uh, no, I can’t.

Yep, I've got all those palms here and love em, don't get me wrong! But a touch of the real tropics is also very appealing. And you know, it's a lot easier to add warmth than to cool things down. But in saying that, if it seems way too hard to get adequate temps for coconuts I'm sure I'll find something else interesting to pop in there that I couldn't grow outside

On 8/18/2024 at 1:54 AM, Harry’s Palms said:

I am one of the few palm nuts that really has no ambition to grow Coconut palms . I like most palms and after visiting tropical places , like Tahiti and Hawaii , I just don’t get it. They look great in the right place , not in my collection. I do miss my greenhouse at my old residence that allowed me to zone cheat various tropical palms but , with a ten foot ceiling , I stuck with slower growing varieties. I did worry that one day even these would out grow the environment . In the winter months I had a heater that I had from my sailboat that would keep things warm , in the summer I would open the upper gable windows and allow the prevailing wind to circulate . It was an ideal environment for palms and orchids . A coconut would’ve taken too much space . Harry

Yeh they are certainly not small plants. But also for me there's nothing else quite the same! I'm thinking I'd need at least 5 or 6m high ceilings to bother at all though.

On 8/18/2024 at 3:35 AM, PalmatierMeg said:

Bottom line, most people would rather bask in their perfect temperate or mediterranean climates composting dead coconuts than move to a more suitable climate to grow them. I get it although sometimes the snarkiness toward us that made the move gets a bit tiresome. The Florida climate is brutal 6-7 months of the year, esp. to older people. Some people have such delicate constitutions that a 50% humidity, 80+F day sends them crashing in flames (just ask my late Aunt Frances from San Jose, CA - oh, wait).

 

Haha yeh, I love the tropical vibe, but where I live now is a pretty great place to be. And I can probably grow one of the widest range of plants in the world here I would imagine. Anything from temperate to subtropical can do well. Just not very tropical stuff. But who knows, most people grow plants that won't grow in their areas, and call them houseplants. It would just need a very particular type of house haha

On 8/18/2024 at 5:23 AM, SeanK said:

If I were to grow a tropical palm in a home conservatory, it wouldn't be a coconut. Too tall, too fast. Maybe Cyrtostachys or Licuala. Start supplemental heat at 50°F.

Fair points! I would've thought cyrtostachys wouldn't survive even with heat to 50F right? Don't they struggle if they get under 20C? At least renda. I did have a thought in the back of my mind one day to try grow one inside, with the roots in a tropical fishtank. Wonder if anyone has tried that? Licuala would probably do good here in a greenhouse even without supplemental heat, potentially. Sumawongii can handle a little cool right?

 

Cheers for all your thoughts everyone! Definitely sounds like it probably wouldn't work without adding a bunch of heating. I will definitely let you know if I do try though. I would probably have to build the conservatory area first and then see what sort of temperatures it would hold before deciding, and that won't be for a few years probably.

Another idea might be Areca vestiaria. Beautiful, and grows at higher altitudes so presumably could manage a bit more cool than coconuts?

[Jonathan]

That's a gold star for answering everyone! 

And yes, completely agree about coming home to a warm greenhouse after a cold day...best of luck with it.

[Tassie_Troy1971]

On 8/16/2024 at 11:23 PM, PalmatierMeg said:

Coconuts are extremely tropical. They demand full sun, high heat (25-30+C), warm nights. Also, they are not only cold sensitive (regular drops to near/at freezing will doom them) but they are also cool sensitive. Cool/chilly temps (below 20C) are lethal to them over time. Cold rain is also lethal. Coconuts cannot photosynthesize below 10C no matter how much sun they get. Cold soil can kill them and given frequent drops to freezing and cool winter temps your soil won't warm until spring.

If you are able to provide supplemental heat (at least 30C during the day, >20C at night) to your greenhouse your coconut may be able to eke out an existence but you must be diligent in caring for it. Don't worry about it growing so large you have to cut it down - it'll be lucky to survive at all. It won't flower or set seeds in your cool maritime climate nor will it do so at elevations over 1,000' altitude.

In any case, go for it and keep us updated on your results. You will add to our body of knowledge about palm growing.

My thoughts exactly I have a coconut in our guest bathroom and the heating is on 24c 24/7  

They can't photosynthesis below around 13c  don't stand a chance in coastal Sydney and even gold Coast Queensland don't look that great.

Was in Thailand a few months ago and the night temperatures all year never get below 20c  they look magnificent there.

 

[Tassie_Troy1971]

On 8/17/2024 at 10:32 PM, PalmatierMeg said:

Totally wacky, I agree. What I don’t understand is after so many years of knowledge people refuse to get it  if you want to grow coconuts move to the tropics or warm subtropics. They will not bend to your desire to commercially grow coconut groves in Kentucky.

I have no right to criticsize as my “impossible dream” palm is Lepidorrhachis mooreana and I have no hope of ever growing one of those even if I could find one.  On the other hand I’ve contented myself with growing this species vicariously. Coconuts are plentiful and cheap, so tormenting and killing them ecologically is easily rectified by replacing them with more fodder. Anyway, have at it.

Years ago, I believed that if I cared enough, worked hard enough, studied hard enough and experimented I would be successful growing palms that common knowledge said I could not (Brahea, Rhopalostylis, Hedyscepe, Jubaea etc). Uh, no, I can’t.

Hi @PalmatierMeg 

I find growing your dream palm Leppidorachis mooreana very easy 

As for the coconut it's inside 😋 

[Foxpalms]

I would suggest a pond in there, it will release the heat absorbed from the day at night, resulting it higher night time temps.

[Foxpalms]

On 8/16/2024 at 2:23 PM, PalmatierMeg said:

Coconuts are extremely tropical. They demand full sun, high heat (25-30+C), warm nights. Also, they are not only cold sensitive (regular drops to near/at freezing will doom them) but they are also cool sensitive. Cool/chilly temps (below 20C) are lethal to them over time. Cold rain is also lethal. Coconuts cannot photosynthesize below 10C no matter how much sun they get. Cold soil can kill them and given frequent drops to freezing and cool winter temps your soil won't warm until spring.

If you are able to provide supplemental heat (at least 30C during the day, >20C at night) to your greenhouse your coconut may be able to eke out an existence but you must be diligent in caring for it. Don't worry about it growing so large you have to cut it down - it'll be lucky to survive at all. It won't flower or set seeds in your cool maritime climate nor will it do so at elevations over 1,000' altitude.

In any case, go for it and keep us updated on your results. You will add to our body of knowledge about palm growing.

I have to disagree with those temps or people on some of the Mediterranean Islands wouldn't be able to grow them even if they are struggling, in Cyprus and the Italian islands.  If the night temps in there can stay in the low 50s -upper 40s as long as the day temps are over 70f I think it stands a good chance at working.

I think there's one in Pantelleria Italy which in Jan is 16c during the day and 13c at night on average.

From looking at others who successfully zone pushed coconuts they either will survive in those warm day time cold night time climates during the winter. High 40s at night and around 70f during the day. Or those cool winter (usually regulated by the sea temps)  but very mild areas where the lows are in the mid 50s with highs in the mid 60s, with the annual low never going below 40f. They definitely won't flower in these climates though. Things such as placing them against a south facing masonry wall in the northern hemisphere, especially a dark coloured one could easily give it an extra 5f during the day which could really make a difference.

Maybe a heat cable to warm up the soil temps would be a good idea, just that as heating.

 

[Foxpalms]

On 8/17/2024 at 3:09 AM, Tyrone said:

 Even when you have all of that you need some automatic system to open vents in the roof to stop the temps getting to Dubai summer heat and cooking everything. I was watching a show about Kew’s palm house and that’s a massive structure (though not as big as the Eden Project) and they have a guy who watches the temp and flicks the switch to open the upper vents at 25C. 

In the conservatory if I don't keep all the windows and doors open it gets way to hot.  Even with all of those open, on a sunny day here it will easily be in the low 40c's in there. When I came back from the canary islands in July I looked at my weather station console and it said the inside temp in the conservatory got up to 149f one day.  That was with one window partly open!

[Merlyn]

There are some Cocos in the Orlando area, where typical winter temps are typically 45-50F lows (7-10C) and highs 65-80F (18-27C).  A few have survived, and @pj_orlando_z9b had his fruit and sprout!

The high temps are probably fine, its the regular low temp is the biggest concern.  As @Tyrone mentioned, small greenhouses very quickly go to outside ambient temperatures at night.  This is just because even good insulated glass is only R2 (U0.5) or so, which is really bad at retaining heat inside.  As you noted, your current small one is only about 3C above ambient at night (at least that's how I read it).  Ideally for a cold weather greenhouse you'd want maximum incoming light transmission (not a low-e type of glass) with argon triple pane, or similar to retain the most heat at night.  That can get pretty expensive, very fast.  Or you can get the best thermally insulated panes and consider supplemental heat if needed.  Glass type and air sealing quality is going to be key to keeping it warm at night.

 

 

[Motlife]

 

On 8/19/2024 at 11:11 PM, Tassie_Troy1971 said:

My thoughts exactly I have a coconut in our guest bathroom and the heating is on 24c 24/7  

They can't photosynthesis below around 13c  don't stand a chance in coastal Sydney and even gold Coast Queensland don't look that great.

Was in Thailand a few months ago and the night temperatures all year never get below 20c  they look magnificent there.

 

Interesting. I might well try one inside where it always stays warm, but I was never too sure how they would do as a houseplant. I'm guessing it doesn't get a heap of sun in the bathroom? Let us know how it does!

 

On 8/20/2024 at 12:18 AM, Foxpalms said:

I would suggest a pond in there, it will release the heat absorbed from the day at night, resulting it higher night time temps.

 

On 8/20/2024 at 12:45 AM, Foxpalms said:

I have to disagree with those temps or people on some of the Mediterranean Islands wouldn't be able to grow them even if they are struggling, in Cyprus and the Italian islands.  If the night temps in there can stay in the low 50s -upper 40s as long as the day temps are over 70f I think it stands a good chance at working.

I think there's one in Pantelleria Italy which in Jan is 16c during the day and 13c at night on average.

From looking at others who successfully zone pushed coconuts they either will survive in those warm day time cold night time climates during the winter. High 40s at night and around 70f during the day. Or those cool winter (usually regulated by the sea temps)  but very mild areas where the lows are in the mid 50s with highs in the mid 60s, with the annual low never going below 40f. They definitely won't flower in these climates though. Things such as placing them against a south facing masonry wall in the northern hemisphere, especially a dark coloured one could easily give it an extra 5f during the day which could really make a difference.

Maybe a heat cable to warm up the soil temps would be a good idea, just that as heating.

 

A pond would be great. I'd definitely be looking at creating a decent amount of thermal mass to hold the heat, but in the winter I imagine it would still not be that warm by the early morning. That's interesting about the one in Italy. Is that outside or in a greenhouse?

The coconuts in California that apparently grew by the Salton Sea also seem like a fair comparison - 22/4C high/low temps in winter. I could probably manage better than that the vast majority of the time without much help from heating. I also know they grow on Easter Island which only has highs around 20C for about 4 months of winter, but also never gets very chilly at night (15C). 

On 8/20/2024 at 5:13 AM, Merlyn said:

There are some Cocos in the Orlando area, where typical winter temps are typically 45-50F lows (7-10C) and highs 65-80F (18-27C).  A few have survived, and @pj_orlando_z9b had his fruit and sprout!

The high temps are probably fine, its the regular low temp is the biggest concern.  As @Tyrone mentioned, small greenhouses very quickly go to outside ambient temperatures at night.  This is just because even good insulated glass is only R2 (U0.5) or so, which is really bad at retaining heat inside.  As you noted, your current small one is only about 3C above ambient at night (at least that's how I read it).  Ideally for a cold weather greenhouse you'd want maximum incoming light transmission (not a low-e type of glass) with argon triple pane, or similar to retain the most heat at night.  That can get pretty expensive, very fast.  Or you can get the best thermally insulated panes and consider supplemental heat if needed.  Glass type and air sealing quality is going to be key to keeping it warm at night.

 

 

My little greenhouse seems to stay 3 or 4C above ambient. But its actually probably less than that, as my outside weather station is in the most exposed spot on a fence and the greenhouse is tucked up under eaves next to the house. And it's not particularly well thermally protected so tends to read low in clear skies and high in the sun. So it would be only a little warmer than the ambient temperature in that spot at night without a greenhouse, I'd imagine. But that's a crappy little cheap plastic thing, that gets opened up every day, and it still reaches mid 20s.

I think with decent design of thermal mass, and considering it would essentially be an extension of the house, I think I could get much better results than nearly ambient without using super expensive glazing etc. I didn't realise how (relatively) cool Orlando was in the winter. It doesn't seem too far fetched to build something to maintain that sort of temperature. 

This would be after we buy a place, in the next couple of years, all going well. I was looking at the official local council weather stations, and the closest one (~2km away) has seen -1C once and 0 a couple of times. One in a hill suburb has seen about 1.5C once and nothing else below 5C this winter. I want to get a place with a bit of elevation, so if our lows were more like the elevated spot it might make the job a lot easier too.

I guess when I do build it it's going to be more about human comfort than the plants, plus coming in at a reasonable budget! So it will be interesting to see what sort of temperatures it will manage to hold, and then if there's any chance at all give it a shot!