Where in continental US never gets freezing temps?

[Kada]

Where in continental US never gets freezing temps?  Seems Florida still gets pretty cold in winters.  How about extreme south?  Is it possible to grow truly super tropical things in continental USA?  I always thought before Florida never froze, but I'm seeing it differently.

[Jani]

Southeast FL and the keys are pretty sure bets to "never" freeze and is a very good environment for growing tropical and many ultra tropical fruit varieties (I use never with some hesitation as hard freezes have happened before but are extremely rare) ...many of this forum's members  are from this area and grow lots of tropicals...So tons of info on here relative to your questions ...enjoy browsing the forum!

[KarenRei]

Define "never".  A 50% chance in a given winner?  A 1% chance?  A 0,01% chance?  A 0,0000000001% chance?

According to this map, the highest zone in the western continental US (if you'd call them "continental") is Catalina and San Clemente islands, just off the coast of LA, as well as a couple LA beaches.  On the east, it's the Florida Keys - 11a Marathon to Key Largo, 11b Key Largo to Key West.  Parts of Miami are 11a as well; After the 11a areas comes 10b: Coastal Los Angeles and San Diego, the area just north of Yuma, and the southmost 5-10% of Florida.

11b means an *average* of 7,2-10°C. 11a means an *average* winter low of 4,4 to 7,2°C.  10b means an *average* low of 1,7 to 4,4°C.  Note that the median zone in Florida is 9b, which has an average low of -2,9 to -1,1°C.  Most of Florida does freeze.  Only the southern tip and keys don't "average" a freeze - but their zone gets so close to freezing on average, you can expect the occasional year to go below freezing.  Depending on your definition of "never", you'd probably include the western keys (there's not been a recorded freeze in modern history), but probably not the upper keys. Small parts of coastal Puerto Rico and Oahu, by contrast, have zones as high as 13b.  That's an average low of 18,3 to 21,1°C.  I'd call that a place that "never" freezes!    I don't think even a major globe-affecting volcanic eruption would freeze that.

Note that zones don't tell the whole story on what you can grow.  For example, here in the Reykjavík area we're in a "warmer" zone than Oklahoma City, Nashville and Richmond.  Yet it's hard to grow here even plants that grow in places like Iowa.  Our minimum temperature isn't that low, but our winter is very long and windy, and our peak summer temperatures very low, which greatly limits what can grow here.  Part of the reason I'm thinking about the concept of doing geothermal root heating   

[JF]

Not very often but it does freezes.

[Guanabanus]

The islands you mention in Florida are all hills on the "continental shelf" and were all part of mainland Florida at lower sea levels.  The "Keys" are mostly Zone 11.

[Daintree]

The Commonwealth of North Daintree, a micronation located in my backyard greenhouse in Boise Idaho, NEVER freezes!
It is the happiest, coziest, most peaceful country on earth. Home to 150 trees, two humans, five birds, and ten million red wigglers.



Happy New Year to all, and may all your "plantasies" come true!

[Paquicuba]

Define "never".  A 50% chance in a given winner?  A 1% chance?  A 0,01% chance?  A 0,0000000001% chance?

According to this map, the highest zone in the continental US (if you'd call them "continental") is Catalina and San Clemente islands, just off the coast of LA.  Zone 11a.  After that comes 10b: Coastal Los Angeles, the area just north of Yuma, and - although it's not really clear - maybe the Florida Keys (again, though, are coastal islands "continental"?  Your call!    )

Fake News!

According to the same exact map [just use the interactive one: http://planthardiness.ars.usda.gov/phzmweb/interactivemap.aspx]
The highest Zone is none of those islands mentioned, the highest Zone in the continental U.S. is Key West (Zone 11b)
Miami Beach is in Zone 11a and most of Miami Dade county and part of Broward and Palm Beach county are in Zone 10b. It's also worth to mention that a lot of fruit and tropical trees need high humidity (A.K.A. Florida's climate)

The SE tip of Florida (excluding Miami Beach & the Keys) have seen freezing temps, but it's sooo sooo sooo rare and so fast that many tropicals have recovered from the damages.

If you're looking for a safe haven to plant tropical trees in the continental U.S., that has never seen a freeze, then Key West is the indisputable winner.

FYI: The lowest recorded temperature in Key West is 41 degrees on Jan. 13, 1981.

[shot]

South of big pine key is best, as adolf grimal told me in 1977 freeze  their was frost on big pine key. Bill whitman had freeze in 1977 and 1989 ,1958 bal harbour.captiva island on our coast is better than miami beach .26 degrees in downtown miami 1917.I was at Grimals after 1989 his bread fruit died back at least six feet so I ask how cold did it get =38

 A good read but kind of nightmarish is the book History of Florida Citrus Freezes
by John A. Attaway

[dwfl]

Issue with the lower keys is salt and soil.

The good thing about coastal south west/east Florida is low temps are quick and dont hang around for hours/days/weeks on end. Usually drop to a low temp early in the AM for an hour and then warms back up. Being on a coastal island (Bokeelia, Captiva mentioned above etc) helps as you are surrounded by warm waters. Miami/Homestead has gotten hit harder in the past by cold fronts compared to these islands despite Miami/Homestead being even further south.

[dwfl]

Define "never".  A 50% chance in a given winner?  A 1% chance?  A 0,01% chance?  A 0,0000000001% chance?

According to this map, the highest zone in the continental US (if you'd call them "continental") is Catalina and San Clemente islands, just off the coast of LA.  Zone 11a.  After that comes 10b: Coastal Los Angeles, the area just north of Yuma, and - although it's not really clear - maybe the Florida Keys (again, though, are coastal islands "continental"?  Your call!    )

Fake News!

According to the same exact map [just use the interactive one: http://planthardiness.ars.usda.gov/phzmweb/interactivemap.aspx]
The highest Zone is none of those islands mentioned, the highest Zone in the continental U.S. is Key West (Zone 11b)
Miami Beach is in Zone 11a and most of Miami Dade county and part of Broward and Palm Beach county are in Zone 10b. It's also worth to mention that a lot of fruit and tropical trees need high humidity (A.K.A. Florida's climate)

The SE tip of Florida (excluding Miami Beach & the Keys) have seen freezing temps, but it's sooo sooo sooo rare and so fast that many tropicals have recovered from the damages.

If you're looking for a safe haven to plant tropical trees in the continental U.S., that has never seen a freeze, then Key West is the indisputable winner.

FYI: The lowest recorded temperature in Key West is 41 degrees on Jan. 13, 1981.

Yep, "zones" are a funny thing. Can't just look at a zone and say this or that species will be fine. Zones do not factor in the climate. Not all 9a/9b/10a/10b etc have same climates/growing conditions/microclimate. There are so many important factors when planting a species other than what your "zone" is.

[pineislander]

Well, you can say that dwfl, shot and I are biased, because we live here, but I think that Bokeelia on Pine Island is about as good a microclimate as you can get in Florida, plus it is a rural environment compared to anywhere close to Miami, and we have better sandy soil than Dade County and far better than the Keys. The largest island offshore in Florida, Pine Island is 32 square miles, Bokeelia lies at the north end and is most likely to receive the first warming breeze from offshore even after a frosty night.
Shhh, keep this a secret, there are less than 10,000 people here....

This is the location:
https://tools.wmflabs.org/geohack/geohack.php?pagename=Bokeelia,_Florida&params=26_41_17_N_82_8_43_W_type:city

Climate details:
https://www.meteoblue.com/en/weather/forecast/modelclimate/bokeelia-helistop_united-states-of-america_4148505

According to the records, we did get a frost in 2000, and in 1982 recorded 23 degrees, but I expect it was of short duration.

[dwfl]

Even in small area of Bokeelia, I've recently seen temperature differences of 6 degrees less than 2 miles apart assuming the weather devices were accurate. Seemed closer to the water the better as the coldest temps were recorded along Stringfellow Rd which runs up and down the middle of the island. You could be frost/damage free in one area and somebody else a mile or two away might not be as lucky. Pineislander, I wonder where the historic weather data device was/is located.

[Luisport]

Ryan Maue | weather.us-Conta verificada
@RyanMaue
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Mais
Record lows likely to the Gulf Coast on Tuesday morning including New Orleans, Mobile ... Little Rock close at 9°F -- and then the Atlantic coast of Carolinas all in the teens. 16°F in #Atlanta.
https://twitter.com/RyanMaue/status/947926675836358657

[Guanabanus]

In 1984, if I remember right, the Fruit and Spice Park in central Miami-Dade county, saw 24 1/2 degrees F.  Way north, eastern Boynton Beach, in Palm Beach County,  saw 28 degrees F.

[fruitlovers]

Issue with the lower keys is salt and soil.

The good thing about coastal south west/east Florida is low temps are quick and dont hang around for hours/days/weeks on end. Usually drop to a low temp early in the AM for an hour and then warms back up. Being on a coastal island (Bokeelia, Captiva mentioned above etc) helps as you are surrounded by warm waters. Miami/Homestead has gotten hit harder in the past by cold fronts compared to these islands despite Miami/Homestead being even further south.

Aren't you a forgetting something? Like hurricanes and tropical storms? According to Bill Whitman the biggest stumbling block to growing tropicals in S. Florida is just that, high winds. Bad soils, salt spray, flooding, and occasional frost don't help either, for sure.

[dwfl]

Yeah hurricanes too. Especially for the keys, salt water storm surge can cover those islands. Wilma storm surge had salt water flooding the entire island of Key West. Irma storm surge this last season flooded some of the middle keys. Alot of plants don't appreciate being flooded with salt water.

Also, while the FL keys and especially lower keys stay warmer than rest of Florida, they do not get the amount of rainfall south FL gets.

[greenman62]

Key Largo
http://www.intellicast.com/local/history.aspx?location=USFL0243

Miami looks like about 4 yrs there have been freezing temps since 1903 (recorded)

Miami
http://www.intellicast.com/local/history.aspx?location=USFL0316

[pineislander]

Pineislander, I wonder where the historic weather data device was/is located.

Lee County Mosquito Control District Helistop on Harbor drive 1/4 mile west of my location.

[BajaJohn]

There are several sources for historic weather records. http://www.intellicast.com/Local/History.aspx is one.
There probably isn't anywhere in the continental US that doesn't have record lows above freezing. Warmest areas are on the East and West coasts where the oceans moderate temperature. The gulf coast suffers mid-continent effects so is more extreme. In addition to Florida, Coastal California is another region that has few freezing days but the dry climate isn't ideal for tropicals and real estate costs are high. Hawaii is the only US state that doesn't get freezing temperatures but it isn't 'continental'.

[KarenRei]

Puerto Rico is at least closer to the continent, but of course still not continental. Roughly the same climate at the coasts, and warmer in the interior vs. Hawaii. However, also very much in the line of major hurricanes.

If you want to avoid hurricanes, salt, and high land costs, and have tons of sunlight, the area on the Colorado just north of Yuma would be your best bet.  But it's not a "never" frost region, just a "most likely no frost in a given year" region.  But beyond the occasional frost burn problem, the Colorado River isn't exactly running an excess in water these days.  One would need to buy up a farm that already has water rights.

[Mark in Texas]

The Commonwealth of North Daintree, a micronation located in my backyard greenhouse in Boise Idaho, NEVER freezes!
It is the happiest, coziest, most peaceful country on earth. Home to 150 trees, two humans, five birds, and ten million red wigglers.



Happy New Year to all, and may all your "plantasies" come true!

Good one Carolyn!     Very few us can create our own, peaceful productive tropical space in cold temps and free of hurricanes and humid suffocating summers.  (We've been in a hard freeze which continues until Thursday)

Hope your project is going well and you're enjoying the fruits of your labors.  I'm harvesting Moro oranges, Meyer lemons, delicious Sir Prize avocados and coming soon, lots of Oro Negro cados.

Remember that multi grafted citrus tree I did in June which I showed you?  Look what i found the other day!  Man is this variegated fruit cool or what.

[Daintree]

Hey Mark, VERY cool variegated fruits! 

The rollinia you gave me seems to be quite happy and has doubled in size. 
I put it down in my book as rollinia deliciosa - that is correct, isn't it?

Stay warm down there!

Carolyn

[Jct]

According to this map, the highest zone in the western continental US (if you'd call them "continental") is Catalina and San Clemente islands, just off the coast of LA, as well as a couple LA beaches. On the east, it's the Florida Keys - 11a Marathon to Key Largo, 11b Key Largo to Key West.  Parts of Miami are 11a as well; After the 11a areas comes 10b: Coastal Los Angeles and San Diego, the area just north of Yuma, and the southmost 5-10% of Florida.

Coastal San Diego almost never freezes, the ocean moderates the cold temperatures nicely.  Go 12-15 miles into the inland valleys and you will get the occasional, although uncommon, frost. The other week Poway had a frost warning, but it didn't get below 40F where I am.  I'm on the side of a large hill, so the coldest air rolls away from me.  Go down the hill to a little hollow and brrrr! Coastal lowland areas have not seen snow since the late-60's.

[fruitlovers]

According to this map, the highest zone in the western continental US (if you'd call them "continental") is Catalina and San Clemente islands, just off the coast of LA, as well as a couple LA beaches. On the east, it's the Florida Keys - 11a Marathon to Key Largo, 11b Key Largo to Key West.  Parts of Miami are 11a as well; After the 11a areas comes 10b: Coastal Los Angeles and San Diego, the area just north of Yuma, and the southmost 5-10% of Florida.

Coastal San Diego almost never freezes, the ocean moderates the cold temperatures nicely.  Go 12-15 miles into the inland valleys and you will get the occasional, although uncommon, frost. The other week Poway had a frost warning, but it didn't get below 40F where I am.  I'm on the side of a large hill, so the coldest air rolls away from me.  Go down the hill to a little hollow and brrrr! Coastal lowland areas have not seen snow since the late-60's.

Lived in coastal San Diego. True it almost never freezes. But still very hard place to grow true tropicals due to many long periods of temperatures constantly below 50F. I also still remember the "June gloom" with long periods of coastal fog. Florida is definitely easier to grow tropicals than California, although still not easy.

[Frog Valley Farm]

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