Jump to content
IMPORTANT ANNOUNCEMENT ABOUT LOGGING IN ×
  • WELCOME GUEST

    It looks as if you are viewing PalmTalk as an unregistered Guest.

    Please consider registering so as to take better advantage of our vast knowledge base and friendly community.  By registering you will gain access to many features - among them are our powerful Search feature, the ability to Private Message other Users, and be able to post and/or answer questions from all over the world. It is completely free, no “catches,” and you will have complete control over how you wish to use this site.

    PalmTalk is sponsored by the International Palm Society. - an organization dedicated to learning everything about and enjoying palm trees (and their companion plants) while conserving endangered palm species and habitat worldwide. Please take the time to know us all better and register.

    guest Renda04.jpg

2018 Florida Freeze


Alan_Tampa

Recommended Posts

I haven't seen my yard in daylight yet, but the damage appears to be primarily some foliage on plants like hibiscus, pentas, etc.  The bromeliads, croutons, etc are looking fine, as are the palms but I haven't seen them in daylight yet. Let's face it, some palms don't show their full damage until weeks later.

According to my thermometer's memory, my coldest night since I bought it is 27 degrees Fahrenheit.  27 won't kill my landscaping but it's the number of hours below freezing and the repeated freezes (four nights this week, including tonight's forecast) that is really worrying me.  When we have a cold snap, that usually means no more than two consecutive nights below freezing and daytime above-freezing temperatures that are not this cold --- not to mention less time below 32 degrees in general.  Oh well, I find out how it all turned out in a month or so. 

Statistically, what are the odds of another crazy cold snap hitting us again this year?  Now that it has happened once, doesn't it mean that the odds are low of a drastic freeze shooting this far south again (at least until next winter)?

Link to comment
Share on other sites

First frost of the cold spell. 33F and frost on top of the car. Lowest was 32F yesterday but every night has been 32-35f. Not earth shattering, but a prolonged cold spell we havent seen in years (2010). Could have been a lot worse considering the severe and intense cold up north. 

  • Upvote 1

Begonias are my thing. I've been growing and selling them for three decades, nearly two in Tampa Bay. NPR is an bhour N of St Pete, coast

Link to comment
Share on other sites

My house in Brandon registered 26 on Thursday morning (with some frost) & 28 on Friday morning, both at about 6:15. Slept in late this morning because the forecast looked better. It was already 39 by 9:00. After a thorough walk through of the yard, I don't see much damage (yet). A couple of bronzed leaves on my semi-exposed  Zamia furfuracea and some fried leaves at the tops of my Carambola and bougainvillea. Under moderate to heavy cover, my Aiphanes minima, Astrocaryum alatum, Caryota mitis, Ptychosperma elegans & Foxtail all look fine, and I think those are my most cold sensitive palms. I also have several tropical/semi-tropical cycads under semi-moderate cover that seemed to do fine. Everything has grown in quite dense with the good weather over the last 6 years and I have had approx. 210 of 6-6.5ft.tall concrete block walls & 2 large concrete planters installed in the last 1 1/2 years, so those things, along with my large Oak canopy, hopefully helped to hold the heat in. I know cold damage can take considerable time to show its ugly face, so I am not cracking any champagne yet, but at least nothing was instantly melted like it was in 2010 (ultimate low of 17-18). And I NEVER celebrate too much until the 3rd week of March.

  • Upvote 2

52% 9B / 42% 10A / 6% "Other"

Brandon.gif

Link to comment
Share on other sites

Thank the good Lord we were spared any freezing temps. 35f was lowest for week and last night was 37.

Ready for Florida to be back next week :)

 

  • Upvote 1

NW Hillsborough County, FL (Near Tampa)

10 miles east of the Gulf of Mexico

Border of Zone 9b/10a

Lakefront Microclimate

Link to comment
Share on other sites

January 2018 Freeze Summary

Jan 4: 31.6f

Jan 5: 32.9f

Jan 6: 34.7f

Those temperatures were all measured from the lanai so open yard must have been somewhat colder. I tested the difference before and it showed open yard was 2.5f colder, but I did an experiment last night that showed it was more like 1.3f. I estimate for the absolute low would been 29-30f. There was light frost on January 4th, but I didn't bother to get up at 7am on the other days to check. 

There hasn't been much damage so far. Out of my palms, my P. elegans has some damage on one frond which is probably from frost. I saw a few others with damage too while I was driving around.IMG_3619.jpg

 

My other palms look fine so far

My neighbor's D. lutescens has quite a bit of browning at the topIMG_3623.jpg

 

That's about it for cold damaged palms around here from what I've seen. The royals might have a little browning on their lower fronds, but the foxtails all look perfect which is a tad surprising. Also surprising, of the 4 coconuts I saw only one had any damage and none of the adonidias had any clear damage.  I predict the coconuts will start showing a lot of damage in the coming weeks. 

Apart from palms, the only damage I saw was to exposed bananas, papayas, and elephant ears.

IMG_3622.jpg

Note how the bananas next to the house still look fine. This is why I always recommend planting the most cold sensitive stuff next to your home, it obviously makes a big difference!

Edited by RedRabbit
  • Like 1
  • Upvote 3

Westchase | 9b 10a  ◆  Nokomis | 10a  ◆  St. Petersburg | 10a 10b 

Link to comment
Share on other sites

In Gainesville, last night bottomed out at 31.5 degrees F, at least by my back garden thermometer.  Starting tomorrow, temperatures should go back to normal, thank goodness.

Link to comment
Share on other sites

On 1/5/2018, 11:11:30, Eric in Orlando said:

35F here at Leu Gardens (previous night was 34F)

31F at my house in Altamonte Springs (previous night was 33F)

No frost last night

Curious to see how the Sabinaria magnifica and the 3 Cyrtostachys hybrids fare.

Astrocaryum aculeatissimum was already showing burn yesterday.

 

Hi Eric... I’m anxious to hear how the palms fared, especially the Sabinaria. Fairly uncharted territory with the cold on that one, isn’t it? Are the palms planted there at the Garden protected in any way or are they on their own (for research sake?)? 

  • Upvote 1
Link to comment
Share on other sites

We really don't do any cold protection here other than moving some containerized plants in or maybe covering some tender bedding plants. Everything else is on its own.. As for palms, I bring in our Cyrtostachys renda into the greenhouse the first time it is predicted to be colder than 46-48F. They get moved into the greenhouse until spring. But this year our greenhouses are missing a good part of the roof because of Hurricane Irma so they got moved into a heated building for this cold spell.

  • Upvote 2

Eric

Orlando, FL

zone 9b/10a

Link to comment
Share on other sites

On 1/5/2018, 1:09:40, Opal92 said:

When was the last time Leu saw a freeze? 2010?

I think so. We have been down to 32-33 since 2010. But I think the 2009-10 and 2010-11 winter was the last below 32F.

 

 

  • Upvote 1

Eric

Orlando, FL

zone 9b/10a

Link to comment
Share on other sites

Lowest temp last week: 38.5F      Pastor Randy, that was probably the same morning you hit 35.

Haven't been able to report any data before now. We were on a 15-day cruise to Central America, but I watched last week's upcoming weather holocaust with great trepidation. Fortunately, we texted our son in Ft. Myers, who was coming by the house Dec. 31, to pull in all my potted uber tropicals into the back room so they avoided the worst of the cold. And there they sit until I return them to their dollies later today. They are dry and I can feel the angry vibes so I will water them well and shower their leaves. Tomorrow I will apply an alternate miticide to ward off inevitable infestations. I hope all of them survive.

A quick survey of the yard yesterday shows most things well but very dry. No rain for 2+ weeks and we had the irrigation turned off last week because of the upcoming cold. Tropical palms, cold and water are a lethal mix for the palms as I've found out the hard way. However, I checked my trunking Hydriastele dransfieldii under canopy in the backyard jungle and so far it shows no sign of cold damage. So glad to be back on land again.

  • Upvote 2

Meg

Palms of Victory I shall wear

Cape Coral (It's Just Paradise)
Florida
Zone 10A on the Isabelle Canal
Elevation: 15 feet

I'd like to be under the sea in an octopus' garden in the shade.

Link to comment
Share on other sites

I was gone for much of this recent cold spell. Thankfully, I was able to move tender stuff into protection before leaving. Our yard thermometer recorded 22 at the lowest. I think 2-3 nights went into mid 20's and 2-3 more were somewhere in the 28-32 range. Not enough to do much damage to Washingtonians, Phoenix, or Livistona. Even my citrus which I didn't cover at all look to get off fairly well with not too much leaf loss. Not terrible considering what others got (especially places normally a little warmer than me (Charleston for example)).

Link to comment
Share on other sites

Looks like the 15th is the next day we could experience a freeze in Central Florida. Currently I have 38f as the forecast so it worth keeping an eye on.

  • Upvote 3

Westchase | 9b 10a  ◆  Nokomis | 10a  ◆  St. Petersburg | 10a 10b 

Link to comment
Share on other sites

57 minutes ago, RedRabbit said:

Looks like the 15th is the next day we could experience a freeze in Central Florida. Currently I have 38f as the forecast so it worth keeping an eye on.

I saw that and was trying to ignore it. 

  • Upvote 2

Tampa, Florida

Zone - 10a

Link to comment
Share on other sites

I certainly hope that there is not another cold snap coming in a week. 

It's amazing that the low temperature for that coldest night was not so different in Orlando, Tampa and the Fort Myers vicinity.  You would think that Fort Myers would be a lot warmer.  

As for points further south, here is what records seem to show as minimum low temperatures for that coldest night, January 4:

- West Palm Beach:  40

- Miami airport:  44

- Miami Beach:  50

- Key West:  55   

The daytime high temperatures somehow crept into the 60s or 70s that week, depending on the day, despite what the rest of Florida was feeling.

8 hours ago, PalmatierMeg said:

No rain for 2+ weeks and we had the irrigation turned off last week because of the upcoming cold. Tropical palms, cold and water are a lethal mix for the palms as I've found out the hard way.

Oh no!  I never turned mine off, although my irrigation mainly hits the lawn, not the palms. It does drench several Livistona Chinensis, however. I hope they will be fine. They look totally undamaged right now.   

I wonder why the central Florida strawberry growers were trying to spray their crops with water just before the big 2010 freeze.  Purportedly, they also had helicopters running overhead, but I am not sure why.   Maybe they were growers located in a valley (cold sink).

Link to comment
Share on other sites

13 hours ago, Eric in Orlando said:

We really don't do any cold protection here other than moving some containerized plants in or maybe covering some tender bedding plants. Everything else is on its own.. As for palms, I bring in our Cyrtostachys renda into the greenhouse the first time it is predicted to be colder than 46-48F. They get moved into the greenhouse until spring. But this year our greenhouses are missing a good part of the roof because of Hurricane Irma so they got moved into a heated building for this cold spell.

Eric,

I have been to your beautiful leu gardens a number of times and I am impressed by your ability to grow zone 10b/11 plants in what looks like zone 9b environment. I figured you must do see one intense cold protection. But now it sounds like ,.. not so much.

I know you have a great canopy in place and you have good plant density. What are the other secrets to your successful zone pushing?

Great respect to you. Now please share you secrets. :rolleyes:

 

  • Upvote 2

Tracy

Stuart, Florida

Zone 10a

So many palms, so little room

Link to comment
Share on other sites

Orlando is zone 10a, but is almost 10b anywhere within a few miles radius of the city centre/downtown, isn't it?

Link to comment
Share on other sites

Just put my tender potted plants back out on the lanai because we're back to lows in the 60s :wub: ...until this weekend when the lows will be in the 40s :rage::crying:

Out in the yard only my banana plants, soursop tree, sugar apple tree, tips of the new growth on the Ceiba trees, and new growth on Tithonia diversifolia are damaged. Sabal mauritiiformis, Pseudophoenix sargentii  and Copernicia baileyana made it through being coated in a thin layer of ice like champs! New growth on the rainbow eucalyptus (near one of the damaged Ceiba trees) showing zero damage :blink: Figure that out! 

Naples (inland), FL - technically 10a but more like 9b in the winter :hmm:

Link to comment
Share on other sites

Orlando is a solid zone 9b with good pockets of 10a in the metro area. Orlando/Winter Park has hundreds of lakes in the area so these help moderate the climate as does the older forest canopy. Add all the overdevelopment and ugly sprawl/concrete and the urban heat island has increased. Leu Gardens is in the metro area and on the SE side of a lake. But the Garden is 50 acres Everyone thinks this is a new thing but Orlando has always had a very moderate climate that gets interrupted every few decades by a killer freeze. Prior to Dec 1983 (when the first of the 3 horrible 1980s freezes struck) there were lots of tender specimens in the metro area; royal palms, large Delonix and Ficus and tender clustering palms like Caryota mitis and Dypsis lutescens. Archontophoenix and Ptychosperma elegans were also seen. Even a few coconuts. I'm interested in history and seen historic photos from the late 1950s and earlier with mature Royals, Coconuts  Caryota urens, even Adonidia and Polyandrococos around. A lot of these old specimens would have been wiped out in the 1957-58 freezes.But the freezes in the '80s not only killed tender, borderline palms but even hardier specimens like Queens, Pygmy Dates, Senegal Dates, citrus and Jacarandas. Norfolk Island Pines and Australian Pines were mostly killed and even Araucaria bidwillii suffered damage. If there had only been one or maybe 2 freezes the carnage wouldn't have been as bad, just severe damage. But the cumulative effect was to great and the 3rd freeze in '89 just was devastating.

The last horrible freeze we have had was Dec. 1989. I have been at Leu Gardens since 1992 and the worst winters since then have been (in order) 1995-96, 2009-10, 2010-11 and 2000-2001. Also, Jan. 2003 had one night at 27F

  • Upvote 6

Eric

Orlando, FL

zone 9b/10a

Link to comment
Share on other sites

"I wonder why the central Florida strawberry growers were trying to spray their crops with water just before the big 2010 freeze.  Purportedly, they also had helicopters running overhead, but I am not sure why.   Maybe they were growers located in a valley (cold sink)."

I believe the theory of spraying strawberries and tender vegetables when a hard freeze is predicted is to shower them constantly with warmer-than-ambient-temperature water that keeps the crops above the critical hard freeze death zone until after sunrise when ambient temps rise. Once the spraying begins, it must continue without stopping all night long or all is lost. That means long, long nights for produce growers. I see that quite often here as SFL is a vital source of vegetables in winter - our principal growing season is Nov. through May, the opposite of northern states.

In the process of spraying, the crops may end up coated with thin shells of ice and even icicles, which seems counterproductive. But the ice acts like refrigeration, keeping the produce hovering just above freezing while protecting it from freeze drying from north winds that come with strong arctic fronts. If the front is strong and long enough, even spraying can't help and you get botanical mass destruction. That happened here in 2010.

 

  • Upvote 4

Meg

Palms of Victory I shall wear

Cape Coral (It's Just Paradise)
Florida
Zone 10A on the Isabelle Canal
Elevation: 15 feet

I'd like to be under the sea in an octopus' garden in the shade.

Link to comment
Share on other sites

Citrus growers do this as well. It is supposed to cover the plant with ice to keep it at 32F & prevent freeze damage at lower temps.

  • Upvote 4
Link to comment
Share on other sites

Before this event it looked like the USDA zones in florida would change a lot when they re calculate them.  All things considered we were lucky it wasn't worse.

  • Upvote 1

Formerly in Gilbert AZ, zone 9a/9b. Now in Palmetto, Florida Zone 9b/10a??

 

Tom Blank

Link to comment
Share on other sites

35 minutes ago, Laaz said:

Citrus growers do this as well. It is supposed to cover the plant with ice to keep it at 32F & prevent freeze damage at lower temps.

In my opinion that is huge mistake. Here in Europe during cold events we always try to keep plants dry. Cold + wet is bad combination. Ice on plants will destroy the cells of the plants. Ice is same as frost. 

  • Like 1
Link to comment
Share on other sites

Running irrigation to form a constant 32°F ice layer has been done for a very long time. It works very well for plants that tolerate 32°F but not much lower. Requires tons of water, which was why micro emiters have been in use in some places. 

  • Upvote 2

Tampa, Florida

Zone - 10a

Link to comment
Share on other sites

45 minutes ago, Cikas said:

In my opinion that is huge mistake. Here in Europe during cold events we always try to keep plants dry. Cold + wet is bad combination. Ice on plants will destroy the cells of the plants. Ice is same as frost. 

Why this process works in FL most of the time is that these arctic cold fronts are usually infrequent and short-lived. The growers are gambling that their desperate measure of spraying sensitive crops will protect them long enough for the sun to rise. Even in winter the FL sun is strong enough to raise temps above freezing very quickly, warm the ground and melt the ice. Once air temps safely exceed the freeze zone, spraying can cease. In Europe your winter nights are cold but your days are also cold and warm slowly if at all. Spraying crops is useless, even counterproductive. Only in historic, rare cases mentioned above do extreme arctic cold fronts break FL's typical winter pattern and cause long term, catastrophic damage.

Also, the helicopters keep air moving around the crops to disrupt radiational cooling that comes on very cold, still nights.

  • Upvote 4

Meg

Palms of Victory I shall wear

Cape Coral (It's Just Paradise)
Florida
Zone 10A on the Isabelle Canal
Elevation: 15 feet

I'd like to be under the sea in an octopus' garden in the shade.

Link to comment
Share on other sites

3 hours ago, Eric in Orlando said:

Orlando is a solid zone 9b with good pockets of 10a in the metro area. Orlando/Winter Park has hundreds of lakes in the area so these help moderate the climate as does the older forest canopy. Add all the overdevelopment and ugly sprawl/concrete and the urban heat island has increased. Leu Gardens is in the metro area and on the SE side of a lake. But the Garden is 50 acres 

I think the lake is what puts Leu Gardens over the threshold for 10a. I saw a lot of the Wunderground stations nearby were freezing and I want to say one was even 29f. Since you observed higher temps I suppose the lake must be what's responsible. 

  • Upvote 1

Westchase | 9b 10a  ◆  Nokomis | 10a  ◆  St. Petersburg | 10a 10b 

Link to comment
Share on other sites

34 minutes ago, PalmatierMeg said:

Why this process works in FL most of the time is that these arctic cold fronts are usually infrequent and short-lived. The growers are gambling that their desperate measure of spraying sensitive crops will protect them long enough for the sun to rise. Even in winter the FL sun is strong enough to raise temps above freezing very quickly, warm the ground and melt the ice. Once air temps safely exceed the freeze zone, spraying can cease. In Europe your winter nights are cold but your days are also cold and warm slowly if at all. Spraying crops is useless, even counterproductive. Only in historic, rare cases mentioned above do extreme arctic cold fronts break FL's typical winter pattern and cause long term, catastrophic damage.

Also, the helicopters keep air moving around the crops to disrupt radiational cooling that comes on very cold, still nights.

Different parts of Europe has different climate. Here in Southern Europe, cold events are also rare. And last for few days. Temperatures below freezing are also rare. Our days in winter time are cool, not cold. But here we never water our plants before cold events. I disagree with that. We also grow different citrus species here, but we always try to avoid ice crystals on plants. Nothing good can happen after ice crystals on cold sensitive plants. 

Edited by Cikas
Link to comment
Share on other sites

18 minutes ago, RedRabbit said:

I think the lake is what puts Leu Gardens over the threshold for 10a. I saw a lot of the Wunderground stations nearby were freezing and I want to say one was even 29f. Since you observed higher temps I suppose the lake must be what's responsible. 

I don't think it really dropped much below 31-32 in this area. I still see green banana and traveler's tree foliage. The bananas at my house in Altamonte Springs mostly burnt out in the open. 

  • Upvote 2

Eric

Orlando, FL

zone 9b/10a

Link to comment
Share on other sites

39 minutes ago, Alan_Tampa said:

Running irrigation to form a constant 32°F ice layer has been done for a very long time. It works very well for plants that tolerate 32°F but not much lower. Requires tons of water, which was why micro emiters have been in use in some places. 

   Right on , and here is a decent explanation of the process .       aka Latent heat of freezing.

http://theweatherprediction.com/habyhints2/468/

Time being the huge variable here .      Also this is quite good for low crops like Strawberries , but on large plants

a long time period will most likely result in physical damage , due to weight .   Used on the lower areas of Citrus trees

to protect the trunk up above the bud line , so that if the top of the tree is blasted , there is the budded variety remaining

to produce the desired variety , rather than the rootstock only being the resulting growth . 

   Here in Volusia County , large Ferneries grow their plants under Shade frame works , and use this technique to develop a temporary 

ice shed effect by sprinkling the shade cloth and forming an enclosure .  Micro jets have greatly reduced the water usage , as Alan said . 

Link to comment
Share on other sites

In my opinion that does not work. Plants that normaly would not be damaged will be damaged because of frozen water. Ice will not warm plants. Ice is cold, and colder the air, colder the ice will be. That whole teory is wrong in my opinion. For example the lowest ice temperature ever recorded is - 346F. Ice does not have a stable temperature. Ice will be created at 32F, but ice can be as cold as - 346F.

Edited by Cikas
Link to comment
Share on other sites

9 hours ago, Eric in Orlando said:

Orlando is a solid zone 9b with good pockets of 10a in the metro area. Orlando/Winter Park has hundreds of lakes in the area so these help moderate the climate as does the older forest canopy. Add all the overdevelopment and ugly sprawl/concrete and the urban heat island has increased. Leu Gardens is in the metro area and on the SE side of a lake. But the Garden is 50 acres Everyone thinks this is a new thing but Orlando has always had a very moderate climate that gets interrupted every few decades by a killer freeze. Prior to Dec 1983 (when the first of the 3 horrible 1980s freezes struck) there were lots of tender specimens in the metro area; royal palms, large Delonix and Ficus and tender clustering palms like Caryota mitis and Dypsis lutescens. Archontophoenix and Ptychosperma elegans were also seen. Even a few coconuts. I'm interested in history and seen historic photos from the late 1950s and earlier with mature Royals, Coconuts  Caryota urens, even Adonidia and Polyandrococos around. A lot of these old specimens would have been wiped out in the 1957-58 freezes.But the freezes in the '80s not only killed tender, borderline palms but even hardier specimens like Queens, Pygmy Dates, Senegal Dates, citrus and Jacarandas. Norfolk Island Pines and Australian Pines were mostly killed and even Araucaria bidwillii suffered damage. If there had only been one or maybe 2 freezes the carnage wouldn't have been as bad, just severe damage. But the cumulative effect was to great and the 3rd freeze in '89 just was devastating.

The last horrible freeze we have had was Dec. 1989. I have been at Leu Gardens since 1992 and the worst winters since then have been (in order) 1995-96, 2009-10, 2010-11 and 2000-2001. Also, Jan. 2003 had one night at 27F

Interesting info- I didn't realize the area had been more zone 10 for stretches of time that long in the past. And in light of the 1989 freeze, I'm sure Leu was a very different place when you started there in 1992. Visiting the Orlando area over the past 15+ years, I've seen the resurgence of tropical/sub-tropical plants quite dramatically. On recent trips, I've noticed Norfolk/Cook Island pines getting to "South FL" height- Large rubber plants, established foxtails, bottle palms.

My family took trips to Disney most years in the early 2000's in February. I remember the 2000 trip being quite cold, 2003 as well. And then I remember our Dec 2010 visit was quite frigid. 

  • Upvote 1
Link to comment
Share on other sites

the latent heat of freezing refers to the phase change that liberates heat.  Its a fact in the laws of thermodynamics, when water becomes ice it releases heat into its surroundings.  The converse is also true when ice melts it removes heat from its surroundings.  So yes, it has worked for strawberries and some other crops, its a fact.  Air conditioning works this way, a phase change that absorbs heat(liquid becomes gas).  The wet down method cannot solve big temperature drop problems or longer durations, but it could prevent plant sap/fluids from freezing just long enough to prevent plant cell rupture by freezing of sap/fluids for  a shorter duration of freezing temps( a few degrees).  Plant sap will surely freeze below 32F as it has electrolytes that create a "freezing point depression" in the water of the plant.

  • Upvote 2

Formerly in Gilbert AZ, zone 9a/9b. Now in Palmetto, Florida Zone 9b/10a??

 

Tom Blank

Link to comment
Share on other sites

23 minutes ago, sonoranfans said:

the latent heat of freezing refers to the phase change that liberates heat.  Its a fact in the laws of thermodynamics, when water becomes ice it releases heat into its surroundings.  The converse is also true when ice melts it removes heat from its surroundings.  So yes, it has worked for strawberries and some other crops, its a fact.  Air conditioning works this way, a phase change that absorbs heat.  It cannot solve big temperature drop problems, but it might prevent plant sap/fluids from freezing just long enough to prevent plant cell rupture by freezing of sap/fluids for thorter durations of freezing temps( a few degrees).  Plant sap will surely freeze below 32F as it has electrolytes that create a "freezing point depression" in the water of the plant.

Ice has no stable temperature. Water ice is created at 0C/32F, but temperature of ice depends on the ambient temperature. If ambient temperature is 20F, ice temperature will be close to that. Snow is also ice, frost is also ice. When ice touches the tissue of plants susceptible to temperatures below zero, cell membranes in the tissue will start to break due to volume growth.

It is very simple, you will freeze to death much faster in freezing water than on dry land. Plus fungus really like wet conditions. Plants always survive much lover temperatures when they are dry.

For example, banana plant will survive much lower temperatures if dry, but it will rot if wet during freezing cold.

People use frost cloth to prevent the formation of ice on the plants.

This Florida practice goes against everything we learn and practice hereDo an experiment with some sensitive plants. Keep one wet, other dry, exposing them to temperatures below zero. You will see that the one keept dry will look better. :)

Edited by Cikas
Link to comment
Share on other sites

Cikas , the ice is constanly melted and reformed as more water is applied. This keeps it in flux, keeping the ice more or less at 32F. Its not a Florida thing. 

  • Upvote 1

Tampa, Florida

Zone - 10a

Link to comment
Share on other sites

fruitgrowersnews.com/article/protecting-your-fruit-from-frost-and-freeze/

 

This has a small section on the topic

Tampa, Florida

Zone - 10a

Link to comment
Share on other sites

Looks like another chilly weekend and first half of the week.  Doh!

Lakeland, FL

USDA Zone 1990: 9a  2012: 9b  2023: 10a | Sunset Zone: 26 | Record Low: 20F/-6.67C (Jan. 1985, Dec.1962) | Record Low USDA Zone: 9a

30-Year Avg. Low: 30F | 30-year Min: 24F

Link to comment
Share on other sites

yep. just as I was relaxing too... man.

Looking for:  crytostachys hybrids, Pseudophoenix sargentii Leucothrinax morrisii, livingstona canarensis

Link to comment
Share on other sites

3 hours ago, Cikas said:

Ice has no stable temperature. Water ice is created at 0C/32F, but temperature of ice depends on the ambient temperature. If ambient temperature is 20F, ice temperature will be close to that. Snow is also ice, frost is also ice. When ice touches the tissue of plants susceptible to temperatures below zero, cell membranes in the tissue will start to break due to volume growth.

It is very simple, you will freeze to death much faster in freezing water than on dry land. Plus fungus really like wet conditions. Plants always survive much lover temperatures when they are dry.

For example, banana plant will survive much lower temperatures if dry, but it will rot if wet during freezing cold.

People use frost cloth to prevent the formation of ice on the plants.

This Florida practice goes against everything we learn and practice hereDo an experiment with some sensitive plants. Keep one wet, other dry, exposing them to temperatures below zero. You will see that the one keept dry will look better. :)

The first statement isn't quite correct in this case.  Ice is stable up to 32F.  Water is stable down to 32F.  Therefore, a mixture of ice and water together is stable only at one temperature....32F.  The comments made about latent heat of melting are dead on.  The process works because when freezing, water releases an enormous amount of energy that prevents the water, ice, and plant tissue from dropping below 32F.  So say the ambient air temperature hits 25F - we choose between having wet plants at 32F or dry plants at 25F (or even lower). 

It was also correctly stated that this only works if you keep spraying - the temperature is only controlled when both liquid water and ice are present simultaneously (Gibbs' phase rule, for the technically inclined - blame it on the day job).  Without water present, the ice will revert to the ambient temperature. 

Steve

 

  • Upvote 1
Link to comment
Share on other sites

  Here is a manual issued by The University of Florida , and SWFWMD , regarding Frost and Freeze protection.

Obviously most palms are too large for this method , but the science is well known , and is , and has been applied

for a very long time .   Much info is herein , and scroll on down , for more .

https://www.swfwmd.state.fl.us/files/database/site_file_sets/42/Frost-Freeze-Protection-Workshop-Manual.pdf

 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Recently Browsing

    • No registered users viewing this page.
×
×
  • Create New...