Generally frost free

[aaronn]

I live in Napa, CA, zone 9b and have been thinking my yard may have a pretty unique microclimate but I haven’t done specific measurements or observations. I work in a technical and regulated field and enjoy just vibing in my hobby fruit growing. I’m on a hill and have a good amount of large tree cover. Sometimes I mutter to myself about the level of shade but over the years I’ve come to appreciate the frost protection. On cold mornings with ice on the windshield out front and frost on the ground behind my property, there is no frost on the ground or plants in my yard.

I mostly grow temperate fruits but do have some subtropicals and am increasingly growing tropical seeds. Last year I left out cherimoya and longan seedlings in pots under deciduous oaks on the slope and they had no damage. Avocados and White Sapote seem to do fine. This year I’ve left out small seedlings of Abiu, Canistel, Jaboticabas, Jack/Chempedak hybrids, and various Garcinia and Annonas. So far, the only dead seedling is a single custard apple seedling, 2 others still fine, I’m not sure the death is necessarily due to cold. One of the Abiu has some cold damage but it’ll be fine. A Geffner atemoya shows some leaf damage, but this could also be further stress from the Geffner struggling in heat waves a couple months ago. All the cherimoyas are doing better than this one atemoya so far. And a cherilata is doing great.

I’m hoping to select a handful of hardy trees to plant in ground in sheltered locations that can still receive some sun. This seems to be a necessary balance I’ll need to observe. Admittedly, I’m early on this journey but I’m starting to think it may be possible to grow many of these fruits outside in my yard in pots that can be moved to deeper shade and shelter in the winter. But it’ll be years yet before I can observe how flowers and fruits handle the winter as I expect these won’t be as hardy as the tree itself.

Even if I remain frost free, it is pretty cold, dipping below 30F based on a weather app. I don’t know how much that changes. Frost formation seems to be more damaging than cold air. I’m sure I can’t grow truly tropical fruits like Mangosteen, Rambutan, or Durian. But a lack of frost seems to be a significant benefit in growing some hardier tropical plants.

Any thoughts or suggestions are welcome! I might get more of a taste for measuring and tracking as I go, but currently I prefer to run a bit wild and free through my hobbies, so no promises, though I appreciate any ideas and who knows what might inspire me.

[850FL]

If your jaboticabas are sabara they will probably be fine. They can take frosts and prefer some shade anyway. I planted one under a crape myrtle this year and it was doing fine until early fall and the sun changed angle, and cooked almost all the leaves!

[aaronn]

If your jaboticabas are sabara they will probably be fine. They can take frosts and prefer some shade anyway. I planted one under a crape myrtle this year and it was doing fine until early fall and the sun changed angle, and cooked almost all the leaves!

Wow! Were the scorched leaves caused during a heat wave? Or did they just seem very sensitive?
I do have sabara seedlings as well as a handful of others like red hybrid, z4, grimal, coronata restinga, and white. I gotta say, I have a bit of a craving for more, but I’m a nut, I’ve never even tasted a jaboticaba.

[nullzero]

Jabo, White Sapote, Macadamia should all do well for you. Would also consider Psidium species and hardier Eugenia species. For annonas would go with Cherimoya and Atemoya. Longan should well long term.

[aaronn]

Jabo, White Sapote, Macadamia should all do well for you. Would also consider Psidium species and hardier Eugenia species. For annonas would go with Cherimoya and Atemoya. Longan should well long term.

Thanks for the suggestions! Good call on Psidium, do you have any favorites? I do have young strawberry and lemon guavas as well as whatever the white available from Four Winds Growers.
I really don’t know much about Eugenia yet. I have a couple Surinam Cherry that are doing pretty well. I had fruit from a friend and found it very interesting. Maybe I need to look more into this genus…
Macadamia! Dang! I hadn’t thought about that at all. Gonna need to give that one some consideration for sure.

[1rainman]

Get some good banana variety like raja puri which tastes better than store bananas and is fairly cold hardy. Plants contain a large percentage of water so when you have large trees or a body of water nearby it helps modulate temperature fluctuations. This is why you have wild temperature shifts in the desert or even in grasslands where there isn't a lot of water filled vegetation or bodies of water to modulate temperature shifts between night and day. I don't think the frost makes much difference, seems to be more about temperature. If its frosting on one side of the yard and not the other its probably a temperature difference though.

[aaronn]

Get some good banana variety like raja puri which tastes better than store bananas and is fairly cold hardy.

I’m a little intimidated about growing bananas. They seem very cool but I’m currently under the impression that they’ll require more care than I can provide. I’m not sure that’s true. Thanks for the suggestion! I will consider it and research raja puri.

Plants contain a large percentage of water so when you have large trees or a body of water nearby it helps modulate temperature fluctuations. This is why you have wild temperature shifts in the desert or even in grasslands where there isn't a lot of water filled vegetation or bodies of water to modulate temperature shifts between night and day. I don't think the frost makes much difference, seems to be more about temperature. If its frosting on one side of the yard and not the other its probably a temperature difference though.

I really appreciate this observation. Somehow I’ve never thought of the trees that are providing frost protection as water reservoirs stabilizing the temperature. I’m definitely early on in my tropical conceptual progress.

[1rainman]

Bananas are easy to grow if you have a hardy variety. Lots of people grow them in the north during the summer then bring them in during winter (the corn ie root ball). They just don't like drought you have to keep them wet. Impossible to over fertilize a banana. Main problem is them having babies and spreading. I grew them in containers in Ohio. At first it was great until they have pups and don't fit. Too much work trying to put a single pup in a new container etc.

They pretty much grow wild anywhere it's warm enough and wet enough. Though there are some varieties like the red banana which are extremely cold sensitive. I had one in a pot before. There are some specialty ones that can be more difficult than others. Wild bananas actually have seeds. Though many domestic ones grow about the same toughness as a wild one or even better like raja puri. Commercial ones are hardy but they are bred for large yields and not for flavor.

[Bush2Beach]

Alot of subtropicals will do well for you.
Some things will grow marginally but not fruit.
Most everything will prefer getting planted out as an established 5 gallon.
People reading 9b that have never been to the north bay /napa/lake/sonoma will not have great guidance on what will do well in your climate. Don’t bother planting Bananas unless you have a year round above ground water source.
Stick to sub tropicals over any tropicals.
The lack of humidity is rough on alot of tropicals and your lows are a bit too low anyhow.
White sapote, mac nuts,loquats, cherimoya maybe, pawpaw, will do good.
Jaboticaba you can keep alive but don’t put them in the ground , keep them in pots with filtered light of oaks during mid day.
Just trading for and getting seeds is a funner way to experiment then buying and killing expensive grafted tree’s that your not sure yet are suitable for your climate but you want to experiment anyhow.

[aaronn]

Alot of subtropicals will do well for you.
Some things will grow marginally but not fruit.
Most everything will prefer getting planted out as an established 5 gallon.
People reading 9b that have never been to the north bay /napa/lake/sonoma will not have great guidance on what will do well in your climate. Don’t bother planting Bananas unless you have a year round above ground water source.
Stick to sub tropicals over any tropicals.
The lack of humidity is rough on alot of tropicals and your lows are a bit too low anyhow.
White sapote, mac nuts,loquats, cherimoya maybe, pawpaw, will do good.
Jaboticaba you can keep alive but don’t put them in the ground , keep them in pots with filtered light of oaks during mid day.
Just trading for and getting seeds is a funner way to experiment then buying and killing expensive grafted tree’s that your not sure yet are suitable for your climate but you want to experiment anyhow.

I think this is great advice, thanks!
I’m hopeful that the trees I can grow will not only be hardy enough to survive winters but will also be able to flower and fruit here as well, but I am concerned that you’re right, survival and fruitful may be two different things.
Man! I really hope my cherimoyas fruit! I’m so excited for them.
I’m curious why you advise against planting jaboticabas? I have enough to roll the dice so I certainly will plant some, but why do you specifically suggest not to?
Definitely trying to just enjoy this as an experiment, mostly sticking to trades and seeds as you mention, but it is tempting sometimes!
Thanks again!

[Bush2Beach]

Some things grow and fruit better in pots in Nor Cal and I think Jabuticaba is a prime example of that.
I have planted out alot, and dug most of them up and repotted them because they have grown so much slower and looked terrible being in the ground.
Definitely grow Jabuticab’s.
I have some fruiting jaboticaba for sale in Santa Cruz if your interested.
Only place north of LA to buy a fruiting Jabo that I know of.

[nullzero]

Jabo, White Sapote, Macadamia should all do well for you. Would also consider Psidium species and hardier Eugenia species. For annonas would go with Cherimoya and Atemoya. Longan should well long term.

Thanks for the suggestions! Good call on Psidium, do you have any favorites? I do have young strawberry and lemon guavas as well as whatever the white available from Four Winds Growers.
I really don’t know much about Eugenia yet. I have a couple Surinam Cherry that are doing pretty well. I had fruit from a friend and found it very interesting. Maybe I need to look more into this genus…
Macadamia! Dang! I hadn’t thought about that at all. Gonna need to give that one some consideration for sure.

My favorite Psidium so far has a Tawainese Emperor type seedling I tasted. Locally sourced the Diamond guava from Exotica nursery are really good. Large superior selections of Mexican cream guava and the Vietnamese green crunch seedless guava are worth it as well.

You have to be mindful on size of guava and ripening period. Some of these tropical large guavas like ripening into November and will slow or stall ripening on cool to cold weather.

I also like Psidium robustum from huertasurbanas,  I tried my first fruits this year. The flavor is unique and better then strawberry guava in my opinion. Any of the Psidium sp. That huertasurbanas gives good review of are probably worth trying.

On Eugenia sp. Surinam Cherry is a good one. If you like sour pitangatuba is another good one. I also like Eugenia luschnathiana. I hear good things about Eugenia lutescens.

[Bush2Beach]

The stalled ripening on psidium guavajava can doom them with rot and splits easily. I haven’t eaten a good one in years.
I tried to kill all my in grounds to the ground.
I hear people ripen them in San Jose & east bay which is hotter and drier in all seasons
It’s worth a shot with less fog and more inland heat.

[K-Rimes]

Psidium guajava *barely* works for me here in 9b much further south than you. I don't recommend them. There are tons of other superior psidiums for you. Long leaf, guinense, "Skittles" guava, and so on. Anything small fruit. My guajavas get burnt back from frost too, lose about 6-8" every year but they grow 1' so it's a net positive. I like the look of them, and they do fruit if we get hot weather in the fall / winter (not this year). Long leaf guava is probably the best for me, overall, and is done fruiting well before it gets cold and is basically same flavor profile as guajava anyways.

I'm probably really similar to you, Bush2Beach can confirm.

Sabara jabo kicks ass for me, in pots. I have a really big one deep in the oaks and it does great. It gets snow on it sometimes and no worries. I don't bother covering it anymore even down to 25-30f. It hit 25f a few years back and didn't even lose leaves.

Success stories for me:

Longan - it loves alkaline soil and water and we have a lot of that in CA. Can't recommend it enough.
Jabo - see above, but forget about reds, scarlets, whites, and so on. Just stick with Sabara and get as big as you can afford.
White sapote - grows fast as heck
Pitanga - they do ok, kinda depends on weather for a big crop. I get tons of flowers but often it rains and that's a no crop situation then
Cherry of the Rio Grande - this is my #1 eugenia recommendation. It is a heavy fruiter and grows extremely fast and takes no damage from frost even visibly on the leaves
Guabiju - in ground through winter (under the guajava) and it's explosive now
Loquats - easiest subtropical fruit tree, for real, just get a later flowering cultivar and you'll really have success. I have one that is a seedling planted in a 10" area between oaks, left it for the laughs and it actually fruits 7 years later! It is in 100% shade.

Things that work marginally:

Mangoes - yeah they can kinda limp along, but not really. They'll die eventually. I still plant them but don't know why, mostly just dreaming that one will survive winter
Annona - they do ok, but not spectacularly. They get beat back by winter too much to succeed
Vanilla ice cream bean - same story, they do well but then lose almost all their new tender growth in a cold snap
Garcinias - they grow ok then die when it gets really cold out, even in the greenhouse mine didn't make it
Jacks - forget about it, you maybe will get flowers maybe even sets but it's not a long enough season to ripen the fruit (I am trialing kwai muk now)
Citrus - does ok, but not really. It would help if the deer didn't love to eat it
Avocado - trialing them first time this year and it's not looking promising, only one is growing marginally well (sir prize)
Acerola - I have had a few make it through winter in pots, but not really. Trying it out in ground now with a big one

Hope that helps

[aaronn]

Thanks for the suggestions! Where could I get seeds of the Taiwanese Emperor type?

Jabo, White Sapote, Macadamia should all do well for you. Would also consider Psidium species and hardier Eugenia species. For annonas would go with Cherimoya and Atemoya. Longan should well long term.

Thanks for the suggestions! Good call on Psidium, do you have any favorites? I do have young strawberry and lemon guavas as well as whatever the white available from Four Winds Growers.
I really don’t know much about Eugenia yet. I have a couple Surinam Cherry that are doing pretty well. I had fruit from a friend and found it very interesting. Maybe I need to look more into this genus…
Macadamia! Dang! I hadn’t thought about that at all. Gonna need to give that one some consideration for sure.

My favorite Psidium so far has a Tawainese Emperor type seedling I tasted.

[aaronn]

The stalled ripening on psidium guavajava can doom them with rot and splits easily. I haven’t eaten a good one in years.
I tried to kill all my in grounds to the ground.
I hear people ripen them in San Jose & east bay which is hotter and drier in all seasons
It’s worth a shot with less fog and more inland heat.

I would say we’re hotter and drier here than the Santa Cruz area so I appreciate the encouragement!

[aaronn]

Psidium guajava *barely* works for me here in 9b much further south than you. I don't recommend them. There are tons of other superior psidiums for you. Long leaf, guinense, "Skittles" guava, and so on. Anything small fruit. My guajavas get burnt back from frost too, lose about 6-8" every year but they grow 1' so it's a net positive. I like the look of them, and they do fruit if we get hot weather in the fall / winter (not this year). Long leaf guava is probably the best for me, overall, and is done fruiting well before it gets cold and is basically same flavor profile as guajava anyways.

I'm probably really similar to you, Bush2Beach can confirm.

Sabara jabo kicks ass for me, in pots. I have a really big one deep in the oaks and it does great. It gets snow on it sometimes and no worries. I don't bother covering it anymore even down to 25-30f. It hit 25f a few years back and didn't even lose leaves.

Success stories for me:

Longan - it loves alkaline soil and water and we have a lot of that in CA. Can't recommend it enough.
Jabo - see above, but forget about reds, scarlets, whites, and so on. Just stick with Sabara and get as big as you can afford.
White sapote - grows fast as heck
Pitanga - they do ok, kinda depends on weather for a big crop. I get tons of flowers but often it rains and that's a no crop situation then
Cherry of the Rio Grande - this is my #1 eugenia recommendation. It is a heavy fruiter and grows extremely fast and takes no damage from frost even visibly on the leaves
Guabiju - in ground through winter (under the guajava) and it's explosive now
Loquats - easiest subtropical fruit tree, for real, just get a later flowering cultivar and you'll really have success. I have one that is a seedling planted in a 10" area between oaks, left it for the laughs and it actually fruits 7 years later! It is in 100% shade.

Things that work marginally:

Mangoes - yeah they can kinda limp along, but not really. They'll die eventually. I still plant them but don't know why, mostly just dreaming that one will survive winter
Annona - they do ok, but not spectacularly. They get beat back by winter too much to succeed
Vanilla ice cream bean - same story, they do well but then lose almost all their new tender growth in a cold snap
Garcinias - they grow ok then die when it gets really cold out, even in the greenhouse mine didn't make it
Jacks - forget about it, you maybe will get flowers maybe even sets but it's not a long enough season to ripen the fruit (I am trialing kwai muk now)
Citrus - does ok, but not really. It would help if the deer didn't love to eat it
Avocado - trialing them first time this year and it's not looking promising, only one is growing marginally well (sir prize)
Acerola - I have had a few make it through winter in pots, but not really. Trying it out in ground now with a big one

Hope that helps

It does help, thanks! A lot of good stuff here. I have friends who grows in the Santa Barbara area and get the impression that we have pretty different experiences. But I don’t think they get snow! So the world is broader than some of these categories suggest.
I’m excited to hear more jaboticaba success and super excited at the prospect of longans; they might be my favorite fruit though I don’t know that I’ll get the same product as what is achieved in tropical locations.
Citrus does well here and I expect the same from white sapote.
Cherimoyas and cherilata are still holding strong, atemoya doing ok. Tiny custard apple seedlings look to be failing.
Tiny Garcinia are doing well but the Achacha has dropped some leaves, might have a problem there.
Yeah loquats, no problem!
Avocado trees are having no trouble at all, hopefully the fruit and flower will do just as well in the coming years.
Canistel seedlings seem fine.
Jack/chempedak hybrid seedlings are darkening, they might not make it. Same with some Abiu. I’m thinking these might be ok if they weren’t first year seedlings. By this, I think that I’m just not exhausted enough yet to admit defeat. Delusion before dishonor.

[850FL]

Kohala longans only hardy to 24-25F in my experience. However I have some seedlings that survived 19-20F. But they are near oaks and a stream so I will have to grow them out a few years to get a better feel for their individual hardiness. Not sure about the other commercial longans.. but I think kohala is supposed to be one of the hardiest anyway. So maybe go to an Asian market and start planting a bunch of kohala seeds from the fruit, same with lychees.

[aaronn]

So maybe go to an Asian market and start planting a bunch of kohala seeds from the fruit, same with lychees.

Thanks! Currently this is all I have going for longans, seedlings of store bought fruit. They don’t mind my winters, but they’re growing slow. I’d love to grow named variety longans but haven’t pulled the trigger on that yet.