Mini Lights Enough For a Zone 5 Climate?

[wxman]

It got up to 29 today for a high which was the warmest in several weeks, so I decided to open all my palm boxes up to see what things looked like. I have to say, I think my palms that only have mini lights and a poly box for protection will make it. We are on the upswing now toward spring and in about 30 days I should be able to pull all my protection. This experiment has been a nail-biter for me. The trachys have been as cold as 18-19F on numerous occasions and barely made it above freezing on the coldest cloudy days. I just can't believe 40 watts of heat per box makes that much of a difference. Well, onward with the pictures!

This one had some early winter troubles. The spear and newest opened frond pulled on New Years Eve. I do not see any further decline though, so I think I'll be able to write it off as a finicky trachy since it's only the first year in the ground. It may not grow as fast this spring as the others, but I'm ok with that.



The other three look to be in mint shape. Spears look great and will not pull.







Now ... on to the foam boxes with the space heater. I have not opened these up since December, so I was definitely curious on what things looked like inside. If you remember correctly, these have a space heater set at 40F, so they have not seen anything colder than 40F since the boxes went on just before Thanksgiving. Before that they experienced one night down to 19F.

This is my oldest trachy, planted in July 2008. It looks visually perfect and I expect it to explode with growth this summer as this will be its FOURTH summer in the ground.



This is a 15 gallon trachy that I planted in June 2010. It didn't do much all summer -- only pushed its spear about 6 inches all summer. It's still green, but looks pretty beat up to me? It was kind of leggy when I got it -- I'm hoping it's just growing roots and will start pushing fronds this summer. Time will tell. I do think, however, that trachys recover from transplant shock much faster the smaller they are planted.



And... finally a pic of what my front yard looks like. Forecast models are possibly showing several days in the 40s the week after next. Could spring be knocking on our door? I hope so.

[ScottyON]

Glad to see that all is well for you Tim. Looks like your experiments are paying off. I wonder how our trachy's are doing (the ones unheated)?? Are you going to switch to the larger bulbs for next year?? I bet that large Trachy will start to look a whole lot better once the warmer weather comes. Next week is kinda cool again but warming up to the 40s they say the following week. We all deserve an early Spring!

[wxman]

I've seen many people who "cooked" their trachys using the larger bulbs. I may just add more mini lights in lieu of larger bulbs as they grow bigger. Mini lights only get warm to the touch, so they are safe on plant material.

I have not looked at my unheated ones yet, but they most likely are dead. Their spears pulled on New Years Eve and we haven't had any warm periods since then. I think you do need to provide heat in Wisconsin -- even though the heat needed is very little.

[ScottyON]

I have the large c-9 bulbs and they are fine. No burn.. I only warp the trunk. The heat rises and fills the enclosure. They also don't run 24/7. They run for about 20 minutes then off for half an hour or so when the temps are around 20f outside. On a sunny day they don't run much at all.. I'll be interested to see what my unheated ones look like too. I'm probably in the same boat as you..

[CTPalm]

I'm new here and haven't yet planted my trachies outside yet. Been lurking in here and learning! Thanks everyone! Do you leave the lights on all winter or just when cold or at night?

[wxman]

I'm new here and haven't yet planted my trachies outside yet. Been lurking in here and learning! Thanks everyone! Do you leave the lights on all winter or just when cold or at night?

I have them on a thermocube which automatically turns on at 35F and off at 45F. Takes the guesswork out of things!

[CTPalm]

Congrats! and thanx - I don't know why I'm so nervous in zone 6

[ScottyON]

The still pretty much require the same protection in zone 6 if you want them to do well and grow larger. There are some that don't heat in the niagara area, but I know that those palms are from BC where most of the ones we get here are from California or Florida which are not as hardy.. If you wrap in lights or heat you palm will look the same all year long. If you don't take those measures they will look near dead when you uncover them in the Spring and take a while before they start to look like a palms again..

[TerdalFarm]

CT,
welcome! You will find a lot of great advice on growing Trachycarpus in your climate on this forum .
Tim,
looking good. I think I'll copy some of your methods for next year with whatever survives the coming week. --Erik

[lucky1]

CTPalm, welcome aboard. Nervous in zone 6? It's good to be nervous, usually assures a bit of extra work done.
We'll look forward to pics of what you're doing.

Tim nice photo update.
Your 3 year old Trachy is in excellent shape, and you'll have to move your sidewalk soon

I still think the minis aren't enough the way you've got them above the crownshaft.
Easily half a "mini line" should be lying on the ground to keep the soil from freezing.
I'd get a longer row, or join two for next year, but that's just me.

Agree with you about the new planted 15 gal ... June didn't give it a lot of time to grow roots, and it has a lot of "plant area" to feed.
Unless you hacked away at the rootball when planting, can't see why it would have a lot of transplant shock.

The size/age factor is an enigma...too small, they're not hardy yet, too large and they're not settled in yet.

Good luck with the spear-pulls.

I'm still missing the P.sylvestris in your yard.
Barb

[wxman]

Barb,

Many people have cooked their trachys feeder roots by placing mini lights on the soil, so I'm not doing that. A very credible poster on the hardy palm and subtropical board states that trachys don't mind frozen soil as long as they don't drop to lethal freeze temperatures (0-5F). In my state, soil several feet down remains 50F all year long, so under the boxes, I bet it's not froze more than an inch or two down at most. I have heat working from above (mini-lights) and heat from below (natural earth heat).

I'm sorry about the P. sylvestris. Just no chance of them being long-term here and I planted them just for the summer, lol. No room inside either as I have tons of bananas and other palms I'm overwintering. Only paid $7 a piece for them, so it's not that costly. I think my ensete maurelii are going to take their place this spring. They are getting bigger and bigger under the grow lights.

[lucky1]

trachys don't mind frozen soil as long as they don't drop to lethal freeze temperatures (0-5F). In my state, soil several feet down remains 50F all year long, so under the boxes, I bet it's not froze more than an inch or two down at most.

There's the crux of the problem...trachy roots have to get down there.
And it's the getting there that's critical.
So young palms are more susceptible because of that cold layer.

Re the 50F common temp, depends on where you are and whether you're sitting on rocks (best scenario), and relies more on an averaging of annual air temps.

The 50 degree constant ground temp is a common misconception. The ground temps vary by location and reflect the average annual temperature of the surface. For example the average air temp over the course of 1 year might be 65 F in the south and so the average ground temperature will be about 65. In a northern clime with an average air temp of 45 F the average ground temp will be 45F. Of course the actual ground temp throughout the year will vary depending on how deep you are measuring. Near the surface will vary more and deeper will vary less.

Even though this is on geothermal, interesting data discussion continues here:
http://www.greenbuildingtalk.com/Forums ... fault.aspx

[TerdalFarm]

Barb,
My entire campus is geothermal heated/cooled; very cool technology.
That was an interesting discussion but the folks were confusing different things, most of which were not relevant to our palm roots.

Tim,
I have a soil thermometer going down 4" by my Chammie. It is buried in snow right now and so not very useful.
My state meterological agency hase online soil thermometers all over the state, including in Bixby, to help farmers. I can get ive online soil temp. data at different depths from this website:
http://www.mesonet.org/index.php/weathe ... emperature
Right now, for example, it is 38 oF 2" under the surface and 39 oF 12" under the surface. Those numbers have not changed much over the past week. The lowest I have seen this winter was 34oF at 2" under bare soil.
I am guessing that each state/province has something like this for their farmers.

I, to, am curious about the effects of freezing on palm roots. I have potted palms in my palm hut. I was counting on the thermocube and heater to keep temps above freezing but I am sure that roots froze in there last week and will again later this week. Given that, I sure am hoping JohnCo is correct!
--Erik

[lucky1]

Erik,
Yes, the link was geothermal discussions, but there was reference to constant ground temps.
And the 3 listed attachments

Attachment: GroundTemps.pdf Attachment: groundtemps1.pdf Attachment: groundtemps2.pdf

from that site give examples of differences when discussing "constant" temps and well as ground temps for USA/Cdn cities.

[BILL MA]

Looking good so far Tim, where almost out of the woods too, before we know it will be pulling off the palm huts

I like your mini light trials for this year. I also did some experiments exposing a 65 gal minor with no protection and a few different needle palm experiments with just roofs no heat. Time will tell for both of us, the snows melting fast here, hope it's doing the same there.

Nice job with your big palms

Bill

[TerdalFarm]

I should probably start a new thread on soil temp.
I've been thinking about it a lot lately.
To follow up with my previous post, this was my favourite part of Barb's link.
[url=http://postimage.org/image/5n10lutg/][img]http://s3.postimage.org/5n10lutg/soil_t ... _depth.jpg[/img][/url]

My original question was, can palm roots survive being frozen?
Now my question is, how deep are our palm roots?
--Erik
P.S. but back to Tim's thread: I opened my Chammie this afternoon to see if the C9 lights (on thermocube) were damaging the foliage. The answer is no. They look great.

<table style="width:auto;"><tr><td><a href="https://picasaweb.google.com/lh/photo/J ... site"><img src="https://lh5.googleusercontent.com/_r-Mv ... 0depth.JPG" height="226" width="400" /></a></td></tr><tr><td style="font-family:arial,sans-serif; font-size:11px; text-align:right">From <a href="https://picasaweb.google.com/terdalfarm ... ">February 2011</a></td></tr></table>

[wxman]

50F is the median soil temp here year round down deep. That's what the temperature averages out to between winter and summer. The trachys with the mini lights were planted the first week of April last year so had an entire growing season to root in. They actually put out 6-7 fronds each last summer so I'm confident they are now rooted well. I'm also sure the frozen ground only penetrates the first few inches in the enclosure and the rootball when I planted them was already at least a foot deep. If the frozen roots were causing them problems, I'm sure I'd see a lot of damage on the above freezing green foliage already since it would no longer be getting nutrients from the frozen (dead) roots.

So either, a) the frozen roots aren't bothering the trachys, or b) the roots penetrate far enough down to supply nutrients to the foliage.

[TerdalFarm]

Aren't you supposed to be watching TV right now?

[wxman]

Packers won.

[hardyjim]

I think the issue with what type of lights etc,
you use comes down to how much insulation you have.


As far as the roots go,some of it depends on the palm/plant your protecting.

Butia and Washingtonia are more root tender in regard to cold then Trachys.

I think as long as you put plenty of mulch around your enclosure you
can buffer the extent of cold soil advancing into your palm hut.

My coldest enclosures(remember the mini/greenhouses?)soil
temps would usually bottom out around 34(F)at 4",whereas the larger
(now collapsible )Cactus g-house would stay around 44(F)
in the center on average-it certainly helps having a large area
covered in regard to keeping those nasty cold/exposed soil temps
from intruding on yer little plants roots.

[lucky1]

Referring to Tim's comment that he doesn't need to keep soil from freezing by laying lights on the ground, would like to know:

Where are Trachy's "feeder roots"?
soil level? or at basal end of rootball?

Barb