It was suppose to be 2010 or 2011, or at least thats what I heard, but I guess not. I definitely think its time for a new map to come out considering its been almost 20 years!

We are technically a borderline zone 7a/6b according to that old map, but we havent had a single zone 6b winter since the mid 90s more than 15 years ago. JFK airport has never had anything less than a zone 6b winter in its recorded history which is something similar to cities in the south. So I think its safe to say that NYC is at least a zone 7a. I wouldnt go as far to say a zone 7b as a whole but some parts of the city definitely are 7b (not sure if they would be large enough to ever appear on an updated map though).

Florida seems to need a lot of detailing done with its zones. Tampa is a zone 9b according to the old map, but there are some coastal areas that are a zone 10a and some inland areas that are probably more of a zone 9a. Some parts of Orlando can definitely pull off a zone 10 since a few coconut palms actually did survive the record breaking cold 2 winters ago. I think that some parts of southwestern florida may also be a zone 10b (right now only the Miami area is a zone 10b and the keys are the only zone 11 in the state).

-Alex

I would also like to see more detailing. When it comes to certain metro areas like Baltimore, Washington, d.c., and coastal New Jersey.

I agree, a Zone 6 in St. Louis, MO gets much colder in the winter than Detroit, Michigan which is north. By contrast, there summers get the muggies for most of the summer, whereas in Detroit, it comes for a week or two at a time and then goes away for another weeks, then returns. We at least get a break from it.

StL-may ultimately get colder in winter but the "palm" season
is a whole lot longer down there.

Click for weather forecast

Click for weather forecast

Washys would love Stl summer weather too-(-:

Click for weather forecast

I live in the suburbs of Washington, DC and I have been growing a windmill palm completely unprotected since 2006. I have never had any defoliation or anything to that nature. I consider my area to be more in the zone of 7a/b but DC proper is certainly a solid zone 8. I saw crape myrtles blooming in late Nov/early Dec in protected areas. Sabal minors have been naturalization around the Air and Space Museum as well.

NYC on the otherhand is certainly not zone 8. This weekend, the forecast low for NYC on Sunday night is 13. DC(by the river) has a low of around 26. Given that it is the same cold front, it seems like quite a difference.

In fact, the coldest it has been in DC is 17 degrees (http://www.wunderground.com/history/airport/KDCA/2011/11/1/CustomHistory.html?dayend=12&monthend=1&yearend=2012&req_city=NA&req_state=NA&req_statename=NA)

We had a significant cold front earlier this year and our low this year matches the low of Tallahassee, FL (18) earlier this year. http://www.wunderground.com/history/airport/KTLH/2011/11/12/CustomHistory.html?dayend=12&monthend=1&yearend=2012&req_city=NA&req_state=NA&req_statename=NA

^^^^The forecasted low for Sunday night is 20F, nowhere near 13.

The lowest I went so far this winter was 14F, which is a zone 8a temperature. I believe that was our only low in the teens. NYC is 200 miles northeast of D.C. so a difference of a few degrees is to be expected even though it's not always the case. I wouldn't call NYC solidly zone 8 nor would I call it solidly zone 7, it's in the middle.

On an unrelated note I see far more trunking yucca than hardy palms, I wonder why that is.

"On an unrelated note I see far more trunking yucca than hardy palms, I wonder why that is."

All the palms are probably covered.(-:

http://forecast.weather.gov/MapClick.php?lat=40.734770989672405&lon=-73.9984130859375&site=okx&unit=0&lg=en&FcstType=text

http://forecast.weather.gov/MapClick.php?lat=38.872859384572244&lon=-77.01484680175781&site=lwx&unit=0&lg=en&FcstType=text

I used the NWS for both forecasts. Sunday night it is 15 for NYC and 26 for DC. Both are as local as you can get.

I do believe that Washington DC has slightly better winters for palms than NYC (I say slightly because usually low temperatures only differ by a few degrees, however we all know that a small difference in low temperatures can mean a lot for plants).

However, you have to see the big picture as well (Data from http://lwf.ncdc.noaa.gov/oa/climate/online/ccd/extremelow.html) ....

Washington Dulles Airport has a record low temperature of -18F (a zone 5a winter) which was set back in 1893.

John F. Kennedy airport's record low is only -2F (barely a zone 6b winter).

However, in fairness, Washington National Airport (much closer to the city center and therefore warmer) has a low temperature of -5F which is still colder than JFK, but it is much warmer than Dulles.

So in conclusion, I think that NYC has some good microclimates that are very close to being just as warm as DC. I did not see a very extreme change in landscape when I went to DC. DC does have many more palms growing without protection than NYC does, but I can still name a few places here where you can see unprotected windmill palms and I have seen pindo palms at large sizes here (given protection). And Crape Myrtles are becoming extremely abundant as street trees and are actually one of only about 50 species of trees that are allowed to be planted as street trees so plants that are symbols of the south are also common here (maybe thanks to DC since the National Gardens in DC is really what introduced Crape Myrtles to the Northern Mid Atantlic Region).

So far I got down to 12F in my yard where my weather station is and my weather station is in the coldest microclimate that my yard has (very exposed on all sides with a white wooden deck that does not absorb any heat).

-Alex

There is a windmill palm that has been growing at the Bronx Botanical Gardens for a number of years now and has never been protected. There are tons of trunking yuccas all over NYC as well. I've seen many yucca recurvifolia, yucca rostrata, Spanish dagger, and even golden sword. I also think that the "micro climate" plays a big role in NYC when planting palms like the needle palm, windmill palm, and sabal minor. I've seen many places where people plant there palms right against south facing walls, which may increase your location by half a zone and in some rare occasions a whole zone. WHO KNOWS. Whatever works for your location.

The maps (regardless of which one you personally subscribe to) are intended to be a general guideline for gardeners. Anyone can zone push by making greebhouses or using covers and lights. But the zone guidelines are for people who don't zone push or winter protect.

I am in Mid-SC, Orangeburg county, officially Zone 8A. Last winter my deep-country location had ONE night with 8B temps at 16-17F. This winter so far we had ONE night with 22F, the rest were 28F and above with most nights at 30F to 65F. Our climate can be defined as more 8B climate or even 9A. Or even as 9B since at least 95% of all nights are above 25F and very few are actually below 30F. One cold night with temps under 20F for a couple hours does not make it a zone 8, does it? What zone would that be? It would be a "29112" zone, matching the zip code. Why? Because every postal/zip code climate is different just like human faces and animal species vary in every continent, every country, every district every forest, every island, every micro-climate. Sydney Australia is zone 8 yet they got kangaroos, but Oregon or South Carolina does not have kangaroos although they are also mostly zone 8. When you travel to Britain or around the world, you can recognise their faces as distinctively "British" or as distinctively "Chinese" and some Chinese even have "dragon features" in their faces with specifically shaped wider nose at the end and dragon eyes etc. We need to create a much more complex system of botanical zoning so to speak.

So far, we must keep in mind, zone are transitional and we must adjust them at least once every 5-10 years. I would adjust zones every 2 years if possible.

I would not include metropolitan areas heat zones in state wide or countrywide zoning maps when making them and map them separately as micro-climatic zones. Ordinary USDA or whatever hardiness maps should be made by measuring temperatures in unaffected countryside areas. Imagine if a nationwide blackout happens for a week, and airplane traffic is zero, what will happen to the cities and palm trees in them? Therefore the only dependable system is to use rural temperatures for climatic maps. When referring to the current USDA maps, if you don't like to push on zones, go 1/2 or even 1 zone lower and you will be safe for many years to come. Fortunately the climate has been warming up (even if they've been spraying the clouds in the sky to cool us down back into the Ice Age) and now many areas have warmed up 1/2 and even 1 zone up. There is Zone 9 in the most of Southern and Coastal South Carolina and Hilton Head Island has Zone 10 climate actually or a strong 9B. Greenville, SC used to be zone 7B, now it is zone 8, probably pushing for Z8B.

As much as I would love to say my climate is a z10a or b, sadly all it takes is one night to kill any of those palms here. Some do survive, cold duration isnt very long but all it would take is one cold winter to kill them out right. Even though most days here would be considered z10a/b. However the urban heat island effect etc do create many micro-climates here that are, even during bad freezes they are usually frost free.

But that wouldnt make a climate a zone more than it should be. The zones do have their flaws for sure. But this is how you can tell a climates true zone, you look at what palms and other plants go their no problem, not at the palms or plants growing in protected spots or at the trending lowest temp a area may see. All it may be is a warm cycle, nothing more. The "all time" record low for an area can tell you just how bad it can get. If you see alot of damage on certain plants, but they come back, your climate is marginal at best for those plants. In a true zone those plants would not be damaged on most winters, maybe only a little on cold winters, but should never be killed or severely damaged.

- US_Marine

Part of the problem with NYC is how long the cold lasts for. If you consistantly get close the the minimum low a palm can support, it will decline.
The NOAA heating degree days is an interesting scale to look at.

All of the data below is from USDA zone 7-8. The only place where people have reliably cultivated palm trees (Norfolk and Raleigh, protected urban DC) have heating degree days at about 4000 or less. I think we place too much emphasis on the zone and not enough on the amount of heat and how long it lasts.

http://www.ncdc.noaa.gov/oa/climate/online/ccd/nrmhdd.txt

WASHINGTON NAT'L AP, D.C. 4055

NORFOLK, VA 3368

BALTIMORE, MD 4720

RALEIGH, NC 3465

NEW YORK (JFK AP), NY 4947

NEW YORK C.PARK, NY 4754

We dont get as warm during the day as DC, but we do still definitely get warm enough for palms to grow.
Plus there are lots of zone 8's in the Pacific Northwest that grow tons of different palms so heat during the winter is not always necessary. The downfall for a lot of plants in Florida during the last cold spell a few weeks ago was that they saw so much mild weather that when the cold came all the new tender growth died because even the most cold tolerant plants have tender new growth.
I agree though, mild winter days are much much better than cold. But I would rather have 50 degree days and then bitter cold for a day than 70 degree days and then bitter cold.
-Alex

I don't doubt that you can grow some species of palm in NYC. I'm just making a point that where I live and where you live (suburbs dc) the zone designation doesnt mean everything; we still need to protect our palm trees.

Good luck with growing palms though. I think we should all be pushing our climate limits. It makes the winters more enjoyable and is a nice touch in the summer.

Every climate is definitely different, even in the same zones. I always consider New York, Philly, Baltimore, and DC to be pretty similar in climate, but DC has always seemed more southern to me in culture and in plants.
I cant imagine not growing palms. I understand why some people dont like protecting palms, but in protected spots I have seen minors and needle palms thrive (I even saw a minor in bloom here this year and mine finally made seeds also this past summer!).
I'll probably always protect my palms. At least if they die I know that I tried my best to keep them living!
-Alex

Without getting into any debate on gardening zones, global warming,...etc., I have to say, that this has probably been one of the warmest winters I can remember in the NYC Metro Area. Despite the current "arctic" air mass over the East, night temps are not brutal and if you look to the extended forecast, we are popping 50F by next week and night lows seem to hover just around freezing point--and this IS the coldest part of the year! Yes, last winter was BRUTAL! It's going to take a while to figure out what the new "normal" is--subarctic cold in Florida and Texas in recent years and record heat in the arctic. Personally, I don't think these gardeing zones have ever been as unreliable as in recent years.

My new "zone map" will only show to what degree/length of time a bucket of water stays frozen in the shade in a given region.(-;

So you get a little pic of a bucket in your region,if it's full of ice your palms are frozen too-unfortunately my bucket stays frozen to long )-:

I think a better indicator than extreme low temps would be your mean temp....there are many micro-climate areas to the north
that although in a warmer zone technically(than some areas to the south) in regard to minimum temps-they may spend 2 months(avg mean) @ or below freezing during winter!

Click for weather forecast

As mentioned above^...... zone map doesn't apply to people protecting palms,although it would give an idea how much protection is needed.

Last winter water stayed frozen in shade for most of the winter here (at least a good 4 weeks because temperatures were consistently below average every day for weeks).
Im actually surprised to see ice this winter when I do see it because things just have not been frozen for long periods of time this year. Some mornings you will see puddles lightly frozen (I only saw them completely frozen during that nasty cold spell in early Jan), but during the afternoon everything thaws out with only a few days as an exception. About a week ago, I had some potting soil in the shade and I needed to repot one of my indoor plants, so I went outside to get some soil and it wasnt frozen at all. Im previous years if I needed potting soil from outside for any reason, I would have to drag the soil into my garage to thaw out a little bit!

Some people are worried that a warm winter may mean a cold spring, but last year we had a cold winter and a very cold start to spring as well so I dont think there is any corelation, but I am a little worried that it might be cold this spring.

Personally, I would really like to see maps also showing how deep soil freezes and the number of hours that an area gets below freezng (that would be especially good for areas like Florida that dont go below freezing too often, but every minute that they do get below freezing could be the last minute of a tender platns life).

-Alex

Yea

I was surprised to see ice in buckets on the north side of the house when temps had been in the 50s for a few days.

Think about the accumulative effect on water in plant tissues being exposed to enough cold to keep a bucket frozen.

I think taking a look at the mean temp is also a great tool in determining what protect a palm-etc-needs.

I do uncover during the day for lower temps esp by February when the sun angle is seriously warming the palm enclosures!
Basically by that time upper 20s and sunny will cause to high of temps inside.

On avg 36F(mean) or higher is necessary to totally remove protection for Trachys,Sabals here for minimal damage.

Would be nice to see palms and aligators in NYC. How about coastal Long Island? Do they have palms growing there unprotected? I've seen Sabal palmettos growing in Outer Banks, NC with protection, so anywhere north of NC must be tough for palms to survive unless they are needle palms or windmills.

I usually take the protection off of my palms around mid February, the latest they have had protection on them is the first week of March. So far my palms have had protection on them for a total of 4-5 days this winter. They may have their protection on for much of this week, but I will probably at least turn the lights off in the protection during warmer days.

Neonrider, there definitely are not a large number of palms on Coastal Long Island. Part of the reason may be because not a lot of people live on Coastal Long Island (some of it is park land and some only summer communities). The eastern end of Long Island gets way too cold for palms because the pine barrens and sandy soil makes temperatures drop like a rock at night. Its amazing how much soil and tree types can affect the surrounding climate (lowing night temperatures by 20 degrees sometimes!)
Coastal Long Island definitely has a good climate for Trachys, Sabal minors, and needle palms. Im sure some homes are giving them a try, but for the tropical look, yuccas are almost always the plant people chose (some landscapes around here plant yuccas and palms which is a nice combo).

Virginia Beach is probably the farthest north on the east coast where Sabals will grow well. Some areas north of that along the coast can probably get palmettos go grow as well, but VB has a pretty good density of palms (I guess partially because of all the beachgoers in the area). Sabal Palmettos grow naturally in the Outer Banks and some parts of the outer banks is actually a zone 9, but a very very windy zone 9.

I went by earlier today to check on the trachys at the Bronx Botanical Gardens and was surprised to see that they were covered by minimal protection. The small one had some leaves thrown on it and the large one had a sheet of burlap thrown on it surrounded by four stakes. This is the first time they protect them . Maybe they have someone new running the show there. WHO KNOWS. 65 days left until Spring - no debate about that. Woohoooo!

Hardypalmfreak

Were those possibly planted last spring?

It may be their first year.

Click for weather forecast

WASHINGTON NAT'L AP, D.C. 4055

NEW YORK (JFK AP), NY 4947

These 2 numbers cannot possibly be accurate.

Washington's temps avg higher in every single month over New York.

No way New York's GDD can be higher.

Jim, those arent growing degree days, those are heating degree days, thats why NYC is higher than DC, DC has less since it gets warmer on average overall than NYC.
-Alex

Jimhardy,

The palms have been there for a number of years now. This may be the first time they are protected. last year they weren't protected at all. Maybe because of last Year's brutal cold blast they didn't want to risk it this year.

HPF

Any pics of these palm????

Oops!

O.K.Alex

Thanks for clearing that up!(-:

Come to think of it those numbers would probably be to high for GDD anyway (-;

When I was a kid, everyone wrapped their fig trees for our 6b winters, but by the 1970s we began having winters with either no snow(which was unheard of) or big snows.

The heat Island effect is strongest at night and prevents temps from bottoming out in extremely over-urbanized coastal regions like New York City. Therefore, when temps have a hard time dropping thru the single digits it boosts the zone. Truthfully, our temps the last 3 years are 8a, but our prolonged-cold(this year the exception), wind, snow still make it unsafe to leave palms uncovered all winter.

Some Yucca Recurvifolias

{{gwi:1167673}}

{{gwi:1167674}}

Yucca Filamentosa

{{gwi:1167675}}

Trachycarpus Takil covered in Pine Tree Clippings

{{gwi:1167676}}

Trachycarpus Fortunei Covered with a blanket of burlap

{{gwi:1167677}}

Trachycarpus Fortunei back on November 7, 2011

{{gwi:1167678}}

Nice pics! Looking forward to seeing an update on those Trachys in the spring. So far this winter is a piece of cake for Trachys, we'll see what February brings. Those yuccas look good too. Last winter's snow made a lot of the older yucca recurvifolias fall.
And whats interesting is that I think some people are starting to get tired of Y. Recurvifolia since I have seen 4 of them get replaced just on my block in the past 3 years. 2 were replaced with knockout roses and the other 2 were taken out when a house was being redone (which is a shame because those 2 were really robust recurvifolias). I like recurvifolia, its invasive, but it looks nice and tropical!
-Alex

I feel the same about yuccas Alex. They look very tropical especially when they begin to trunk.

I think USDA Hardiness Zone system is imperfect. As some people wrote on here, a Zone 7A in NYC is not the same as Zone 7A in North Carolina. The low temperatures can be the same, but DURATION and FREQUENCY of those low temps can make a big difference on plants. For example, if NC in Z7A gets 2 nights with temps below 10F, then NYC/NJ in Z7A would most likely get many more of such nights with temps below 10F and those night lows in NYC/NJ would most likely last for more hours than in NC. Plus there would be more hot days in NC than in NY. So why don't USDA rework their hardiness zoning system into something more useful. How about splitting each zone into 10 zones, so for example zone 6 would become zone 60 through zone 69 or 61 through 70 and every decimal zone would become a zone on its own. So then an ex-Z7 in NYC would become Z71 while ex-Z7 in NC would become Z77 and so on. Even ex-Z7A in NJ would not be the same as ex-Z7A in NC (North Carolina). Plus they must also include HEAT ZONE coefficient into the creation of new zones. A letter could be added to the zone number, for example: Z71A vs. Z78H would mean that Z71A has more frequent and longer lasting nights with typical low temps, plus it would have less days above 86F and Z78H would have less nights with typical low temps, with shorter duration and more days with over 86F. So all those new zones would count the DURATION & FREQUENCY of low temps and HEAT ZONES (duration and frequency summer highs, which is especially important for many palms, since palms survive cold weather (are/become more hardy) better after being exposed to a hot summer weather year after year) into the establishment of new plant hardiness zones.

novaplantguy - Charleston, SC is Z9A. Check out the link I provided below.

Here is a link that might be useful: Interactive USDA Plant Hardiness Zone Map

if I use that map it says I am a zone 6B -5 to 0. I havent seen anything below 15 degrees in almost 5 years which would mean I would be maybe a 7B. I mean they can say your zone this or zone that if you have lived there long enough you should know how cold it usually gets after a few winters. I know it was a old post but if hunter M is still on here I don't live to far away get at me and we can do some trading

Haven't seen Hunter on in ages. His palms all died (probably from too much attention) and got all discouraged.

Two things: All who live in big city's and have for decades will tell you..low temps are higher then ever. BUT,you still have to know your area. As the classic book "How to lie with statistics" says, both the Catalina Islands AND Palm Springs have a annual mean of 61f!

well I am close to where he moved and its a pretty backwoods area figured I could help him out but if he dosen't get on anymore I can't. thats a ruff place hope it didn't get to him

Miketropic - USDA 2012 Plant Hardiness Map is for 1976-2005. Since then at least 7 years have passed. You could as well be in a zone 7A or 7B, but if you have not seen below 15F in 5 years, so for those 5 years you are in zone 8B. Yet I have no idea where you are as you don't have it on your profile. Where I am in mid-SC it used to be zone 8A close to 7B and now it's 8A close to 8B but judging by the past 3 winters we are having zone 9A/9B here. I'm "afraid" zone 9 has moved to a large part of South Carolina. One night of 22F, then 3 nights of 25F and some 28F, the rest above freezing. This autumn we did not have frost yet. Last year first freeze was in the end of December 2011 and it was about 25F. Yet I remember one night around 2007 when we had 13F for a few hours. And if those artificial contrails in the sky become plenty, that will affect the hardiness zones as well. You are right, if one lives long enough in one place, they know better what zone they are having there.

I live in Kentucky, the northern part. the zone map has it as a 6b and it does get pretty cold here. we have had 25 degrees already a few night. our coldest time is in feb. and we do see some cold days and nights but for the last 5 years the coldest I can remember was 12 degrees one night in march and a zone 6b puts us a 0 thru -5 and that hasent happened. I do wish they would update that map a bit more even though I kind of know what to expect anymore.

That's the problem with the zone map is that its based on the average lowest annual temp. We can go years without dropping below 20 but history says we've had single digits in the 1980s. If we ever have one of those especially cold blasts no map will save plants that will only survive into the upper teens.

Haha, I love the link that tropicalzone7 has posted (I include it below as well). That's a great Reality Check for most growers. :-) It's like having lion as a pet. Some day you will get eaten by your pet. Some day, and for now, enjoy it. Hopefully that page gets updated every year or every time a new low is registered, although unlikely so in the past years.

Here is a link that might be useful: Your Reality Check

Lago, not sure about single digits, but WC/ weather.com is showing -3F as record low for VA Beach in 1985. That would ruin many a garden there.

http://www.weather.com/weather/wxclimatology/monthly/23462

I think that record was actuallyat Norfolk Intl which is the nearest official airport. Suffice to say it was brutally cold and many a plant must have expired. There are palms in the area that survived through it.

More likely Oceana NAS, since Norfolk's record was even lower.

It's hard to tell anymore what zone we all are in. So far we had zone 10A weather in South Carolina. Last winter was zone 9B weather, except one night with 22F (Z9A). What zone are we in? 7A, 7B, 8A, 8B, 9A, 9B, 10A ? No one knows anymore....

I stay pretty conservative when using zoning. Our record low in Lakeland is 20F. That's a worst case scenario zone 9a.

I wouldn't go by the lowest temps that have been happening in recent years. I think thats where part of the problem is with the USDA zones. They only used part of their data. Although they do have a reason behind it, I still think that for the areas that do have more data they should have just used them anyway. Thats too small of data to be very accurate in my opnion and do not take into account if they have been recording a warming or cooling trend. And if thats the case are they likely to continue? And what about record cold winters and how often they will play out? Its hard to say.

But what I like to do is look at as much info as I can and take the average of all data collected about each years low in an area. I tend to think it is more accurate and gives a better picture of whats going on and what to expect. The USDA is just one tool or a guide to help you out.It may have its erros. But at least it narrows down the list and keeps those that don't know so much about gardening from wasting money on things that will never have a chance.(although that doesn't stop people like me from zone pushing or trying anyway. lol)It was never meant to be set in stone. Each year is different and so is each area. Best ways to truely understand your zone/climate is trial and error. As well as looking around and see what other people are growing long term.

But I am down for a better system. Anyone else? lol Unfortunatley I don't think any system will ever truely be accurate. Theres just too much to consider other than temps. Youn have soil, elevation, moisture, health of plant and list goes on. And not to mention each local micro-climate...

- US_Marine