I have a friend in a smaller town about 20 miles from me. She lives "in the country". By this, I mean, out on about 40 acres of land with no concrete, no paved roads and very few other houses around. Therefore, in winter, when its 35 at my house, even though we are in the same zone (8B) and only 20 miles apart, it may be as much as TEN degrees colder at her house.

She has a 2000 sq ft greenhouse but its crammed full.

Tender plants that she has planted outside, including a few palms, she does EXACTLY what you said (and so do I, with some small growing heliconias and alpinia purpuratas)...erect a PVC and Poly film structure over it, stick in a ceramic space heater, and let her rip. I make mine with a flap that can be taped down, and then lifted up the next day for ventilation.

We leave these structures in place until March, cuz its too much work to put up, take down several times, even if we only have toheat them 3-4 times a winter. One extremely nasty winter we had a string of 22-29F nights for 10 straight nights. That was several years ago and thankfully has not repeated itself.

On some things that are very close to the house, a heat lamp (100-150 watt bulb) or a string of Christmas lights inside the enclosure provide enough heat.

Orchiddude,
The one thing you have to keep in mind when it comes to building a mini greenhouse, is overheating. The temp. will quickly rise inside the enclosure and cook the palm, unless you open it up every morning.

Most people in the south use C9 christmas lights and frost cloth to protect their marginal palms. You can keep a palm wrapped all winter this way and not have to worry about overheating. This method, depending on the cloth weave can add 5-15 degrees of protection. On extremely cold nights you can cover the wrapped palm with plastic for added protection, but make sure you remove the plastic when the sun comes up.

I have always used greenhouse shade cloth to cover my marginal palms, and I cover them with plastic if an ice storm is forecast(To keep them dry). This method has worked well for me over the years with plants like Livistona chinensis, Phoenix canariensis,and Washingtonia.

Yes, opening up the enclosure when the sun comes up is KEY. That's why I construct mine with an easy open tape flap. And so is using a heater that has a thermostat and will turn itself off after the preset temp is reached. I set mine on the lowest setting. Its one that blows warm air over the heat block and oscillates.

I use the same type of heater to heat a 90 sq ft "portable greenhouse" (one of those steel frame/12 mil poly cover pop up jobs) and it works really, really well. This pop up actually has zipper roof vents, a zipper door and a back wall vent that have to be opened up first thing in the morning after the heat goes off.

So, each day you take off the cover so the palm can get air, light, etc... correct? What about the cold. Do you montior the daytime temps. I dont think it would be a good thing for a palm to go from 40°F in its box, and then being hit with 25°F when you lift the lid. FREEZER SHOCK is what I call it.

One other question. For those using protection in the zone 6's and above, this cover and uncover must go on and off day after day. RIGHT? or do you cover and leave it covered. I can understand a zone 8 covering a few nights and I know in my zone 7, sometime we have a whole week where it might stay in the 30's at night and 40's in the day.

I guess I am going to just have to play with one of the plants some winter, I just keep thinking, there is no way, I would put my big spindle palm out in the cold and it get killed by my negligence, on some techicality, that I forgot to do. I would be sick, to say the least. Do you know how many people in AL have a spindle palm as big as mine, 0 to none.

I know maybe next year I can get a PR and plant it in the ground, and try this. It would be a learning experience for sure.

orchidude - I would not try any overwintering method on a plam I would not want to lose. Experimentation is the best teacher. (again, preferably with palms you don't mind losing). I agree with dwayne 4117, probably the best protection is the C-9 lights with a frost cloth wrap.
It depends on what your trying to overwinter, but having the lights on all the time is not a good thing either. I only use heat when the forecasted temperature is nearing the bottom of what I have read is the low end of the temperature scale for the palm.

I will also cover mine with plastic when rain or snow is forecast. Best to keep them as dry as possible.

Good luck.

oppalm......I promise, I wont try anything on my plants. I have put too much work into getting them the size they are, and the years, I was thinking about how long I have had some of these plants. Years and years and years. Next year I might try getting something and playing around with it.

why next year, do it this year. Go to a big box store and get a phoenix roebeleni (or something else cheap) and plant it in the ground in its container. wrap with frost cloth and small christmas lights. Keep an eye on the forecast and turn on the lights when temps are going below 25. cover it with plastic if it rains or snows. do whatever else you have to do if it gets really cold. I'll guarantee you will learn something about protecting palms if you do it this year.

You make it sound so damn easy. LOL

Let me think about it. :-)

Thinkin' time is up. you've had about 4 hours to think about it. get er done. Its really not that hard, especially if your doing just 1 palm. Live large.

LOL oppalm, your funny. I will look and see what I can find. I think Lowes has some CID in 5 gallon. I will look and see.

I'll be experimenting this year. I have two needles, 4 Sabal minors, One Trachy, and one poor Washingtonia in the ground. I rescued the Washingtonia fiom A pet food store that doubled as a tropical nursery. I paid 10 bucks for it. I've butchered it alreay. I nursed it back in a pot all winter. Then i put it in the ground not factoring a Lilac tree which ended up blocking the sun. I moved it about two months ago and Now I have a steroid driven tomato plant that's about 8 feet covering it. The spear is out and getting sun but most of the plant is covered. I'd pull down the tomato plant but I'm getting a bumper crop of 14 oz orange tomatos. They look like the giant beefsteak except they're orange. I have chicken wire to put around all of the palms I mentioned. I'm going to fill it with pine straw first and then add some maple tree leaves when it falls WAY below freezing. The Trachy and Robusta I will put x-mas lights around.

Has anybody experimented with those heating cables you put around pipes to keep from freezing?
Was wondering use copper pipes as stakes around palm,then surround it with these heating cable.

Orchiddude I've been asking people this same question lately. Several people have told me about a device called a thermocube which is plugged into an electrical outlet. You plug your heater, heating cables, or c9 lights into the thermocube. The thermocube turns on when the air temperature reaches 35 and off when the air temperature reaches 45. Apparently a lot folks are having good success with a thermocube, c9 lights, and frost cloth to overwinter tender outdoor palms, pretty much like Dwayne described. I'm going to give this a try myself this winter.

http://www.thermocube.com/

Is this what you are talking about?

Rob

Hey those thing look pretty cool. I just ordered 2 of them. No more turning the lights on and off at night, its all automatic, unless of course your anal retentive and have to go outside every night during winter and check to make sure the lights/heater cables came on at the appropriate temperature and that your plants/palms or OK.
Who says this isn't fun?

Can anyone tell me what's the best temperature to keep a pygmy date palm (Phoenix Roebellenii) at during the winter in a greenhouse? I don't want to go too high due to heating costs so please keep that in mind.

I would say 50s to be safe and I would think very little watering is needed when that cool. You do want to make sure it never falls near freezing. The leaves will dry up. I know they origianlly come from flood plains in Thialand. Try researching Thialands weather.

I know from experience that I kept my greenhouse around 55°F last year during the winter. My palms didnt have a problem, except my bottle palm and I kept it too wet and it rotted. So this year, I do something differnt with them. Another store, anyway, the (Phoenix Roebellenii) does great at that temp and I do cut the water back a little, but I have found out that they want to keep growing and dont slow down as much as some of the other plants, so you have to water a little more. Mine tend to dry pretty fast in the greenhouse, so I am watering about once or twice every 2 weeks or so. If you let them dry to much, they will drop leaves fast.

Why do some people up north protect their in-ground palms with simply xmas lights and a cover while some others build greenhouses surrounding the palm? For me, I was planning on going the greenhouse route, but this is something I'm starting to second guess myself on. For one, the greenhouse is going to cost loads more than just xmas lights and a cover, as well as the cost to heat the greenhouse in the dead of winter. Does anyone have any suggestions about what method is more feasible for protecting a phoenix roeb? I just don't want to spend all this money when I could protect the palm much more simply and cheaper.

Thanks!

Greenhouses are more than palm protectors. Greenhouses are live, breathing, working,mean, green growing machines that have a life of their own.

oppalm....what palms do you grow. I dont think I have seen your pictures yet. :-) I am sure you have something good to show.

orchidude - I'll post some pictures in a day or two. I don't have access to them on this computer. I've been into palms about 3 years and grow about 20 different kind of palms. I have posted some pictures on the banana forum of my bananas and tropicals. I'll get them posted here.

Ptmcclanahan-
Some people use X-mas lights, Mulch, and burlap, and others on more cold hardy palms. Needles and Sabal Minor one can get away with minimal protection (zone 5b-6b) simple mulch will usually do. A Trachy will certainly need some sort of heat source (x-mas lights being the most common) A Roebellini on the other hand is another story. No protection short of a greenhouse is going to keep it alive. I've never read on this forum of anyone in our type climate trying it and David Franco auther of "Palms won't grow here" has said himself he has had no success with overwintering a Robellini using the techniques he describes in his book.

Haven't read his book but plan to soon. Did he try overwintering with a greenhouse or what was his method? Regardless, as I've said many times before here on this forum, it's a $25 palm, so no worries on my part.

Roebellini are one of my fav.... I am going to grow 2 of them in the ground here starting next spring, and then build mini greenhouses around the during the winter, use a small heater etc.. to keep them going. I have been thinking of a cool little design where I can pop the top without having to take it down during the day. Will see next year.

The thermocube looks really cool. I only wish there was one that would turn on at 45 instead of 35.

J

I know jardinerowa...I was thinking the same thing. Maybe the people that make them have a line of higher temp switches.

orchiddude did you get the other palms I sent you ?

Wow.....lots of good suggestions and great ideas. The Christmas lights sound like a good idea, BUT...that's only if cold air is your only issue. What if there's snow or freezing rain (ice storm)? It doesn't happen much in the South, but it does happen. The only parts of the palm that will be spared any damage would be those areas close to the lights.

Orchiddude,
We live in the same zone, and you know as well as I do, we got off lucky last winter. Not harsh at all (except for the ridiculous jump in LP/natural gas prices!), but who knows what this season will bring. Building an individual green house over each outdoor palm sounds a little labor-intensive for me : ) I vote for andyandy's method. That's what I used for my palms, and they overwintered fine. Go to Lowe's or Home Depot and buy some polyfence...sometimes called landscape fence. Put stakes around the palm, cut the fence to fit and form a basket around the plant. Fill with leaves/pine straw, and Voila!...you're ready for winter. Just remember to pretreat the palm to guard against fungus infection.

One final thought....my palms are still small. If yours are rather large, frost cloth/lights or a mini-greenhouse may be your only options. Polyfence only goes as high as 4 ft.

david....yes, they look good. Thank you.

wingo....sounds like a good idea. My thought was if the plant was say 2 foot off the ground, I would build a small rectangle type box with styrofoam around the sides, maybe 2x4's in the corners, just a box, put some clear poly on the sides and top, place over plant, attach to ground, have the lid so that I could just flip it open on those sunny days. Kinda sounds like over kill for a palm but the idea is to keep it warm, or just about freezing. Who knows, thats next winters project, this winter project is to revamp my greenhouse. I am almost done, its looking good.

orchidude - how about a picture of your greenhouse? you could put a palm in front of it. I need to do a greenhouse in the next year. gotta start looking. I've been on the greenhouse forum and reading threads, getting advice and ideas.