My question is...do I need to protect the new growth and recover?

Yes, you will get die back. The temp will kill all the green growth including buds.

Would simply covering with a cotton sheet help protect the buds, or should I go heavier with a heavy gardening plastic?

The plastic my not be enough. The whole tops could die because your tree now has come out of dormancy, thus the antifreeze it has within its cells from what I remember is gone. A plastic with some old type christmas lights or heat lamp. If you cover with a plastic cover the entire tree in a tent style and cover the edges with dirt.

I agree with loslunasfarms. Plastic doesn't offer much insulating value. Wrapping in an old blanket or quilt underneath the plastic would help.

Loslunas and Fignut,

Thanks for the quick opinions.

Anyone else like to chime in? I have two Celeste Figs that I purchased and planted last year. They put out about 50 figs total which surprised me for the first year.

Being that it was above 70 a week ago, I uncovered the plants and the buds all seem to be in tact with some having a hint of green. I do not regret uncovering them because there was slight mildew that would have worsened from the warm temperatures.

Over the winter they were wrapped with blankets and then a black plastic bag, kept open under a bucket atop. Would this be a good approach to protect them from the cold spell? Thanks!

figgi11,

This approximately the method that I used during this winter (my in-ground's first winter outside). I wrapped with attic insulation, covered with black plastic, and then used raked leaves in those large brown bags to surround as a wind barrier.

Geoff

Thanks for the feedback. Too bad there's no outdoor space heaters for plants that you can plug in to keep the plants safe overnight!

I agree 100% with loslunasfarms. Lights work well under a covering and that added heat helps prevent damage. Personally, I like to use a spot lamp or a work light with a high wattage bulb. Make sure that the lights are not the newer LCD type bulbs......those do not provide enough heat.

Dan

Today was pretty windy, and if it stays that way overnight I don't think lights will be enough unless the temperature doesn't drop very far.

Fignut,

I might be wrong in my assumption, but I'm not necessarily worried about the wind at this time. I'm more concerned about the freezing temps. As long as it doesn't drop below 33'ish, I think I'll be okay. That is, tonight is supposed to drop to about 36 F and windy...I'm more concerned about the 21 F forecast for Friday night.

Am I wrong in this assumption?

No, you are right. But I'm not talking about desiccation due to wind. It's that heat is lost more quickly from a structure if it's windy, and a light bulb doesn't produce a lot of heat. It should be fine tonight if the temperature doesn't drop very far, but Friday night might be a problem - especially if it's windy.

A plastic helps to contain the heat, burying the plastic around also helps to capture the heat. The light bulb or small heat lamp helps keep the temp above 32F. I have kept my Apricots from freezing using this method. The problem is that when it warms during the day you have to be sure to remove it (if clear) otherwise the heat shield turns into a greenhouse and bakes the tree.

Aint' pretty but it works.

All you are trying to do is keep the temp above 32-33F and frost from forming on leaves.

What is the lowest temp - outside the plastic - that this has worked?

Any thoughts about using a ten-gallon jug filled with hot water (instead of lamp) to keep the temps up through the night? I think I've seen this written somewhere before, but not sure if it works. I know that water is a pretty good insulator and holds heat well.

Thoughts?

Fignut,

I've done this only this year, and it worked just fine. What ever our lowest temp was this year was the lowest temperature that it worked to...probably around 5-10 F...but I'm not sure.

I think, though, that this is only half of the answer. It really depends on the cold hardiness of your tree.

Geoff

The temp for me is around 24F or -5C.

With the light, it is much lower.

The ten gallon jug with hot might best work. It should be in a tent. The amount of calories energy release are ~2384550 Calories for hot water to go to freezing.

-jbs

Loslunasfarms...thanks a bunch for all of your help...I have to get geared up for tomorrow night when the temps will drop.

Thanks,
Geoff

I have used a small heat lamp from walmart for about ~$14. Just like the kind you use for chicks.

Please post pics, before and after geoffs. This information sharing is very useful.

One can also use a compact size Halogen Worklight (pretty cheap at places like Harbor Freight) using a 300 watt quartz bulb......gives good amount of heat under the tent.

Dan

I agree with Dan, I like the heat lamps cause they warm the surface, not the air. The tree keeps warm. This I have verified on my Apricot trees.

Sorry, Geoff, I wondered how cold loslunas' temperatures got outside the tent. I'm not a big fan of plug in heating during potentially deadly temperature drops - Murphy's Law applies. I don't have in-ground trees and have never tried lights or heaters, so have no experience with the tecnique. And I wondered how cold it could get for the light bulb still to work. I should have been clearer about who I was asking the question. I do like the hot water idea better than plugging something in - less chance of mishap involved. Just me.
But there are two different situations. Protecting a dormant tree over the winter as opposed to protecting a tree that is no longer dormant. The dormant tree will tolerate below freezing temperatures (as yours has) and the cover (or other protection) slows down the temperature drop allowing the tree to adjust to some pretty low temps. I've had uncovered trees in my garage get to 10 degrees without damage. A tree that is out of dormancy will not tolerate freezing without damage.

loslunas, we are expecting in the vicinity of 21 degrees F Friday night. What I was wondering was how much of a heat boost the light gives over outside temps. If we get 21, we'd need at least a 12 degree boost. Is that likely?

Sorry, I left my above post while I was writing it, and didn't see your post on radiant heat before I posted it, loslunas. There must still be a range for radiant heat to be effective though.

A key learning here is that; whenever an outside fig tree has come out of dormancy too soon and is threatened by a brief cold spell,......damage can be avoided by the use of a tent and adding some radiant heat under the tent. Like Jose says.......radiant heat...heats the tree and not the air. Not all heat is the same.

Damage to exposed fig leaves occurs thru radiation heat loss thru the unprotected leaves of a tree. A 300 watt quartz bulb provides quiet a bit of this type heat and can protect a tree from a late cold spell. I have given a more detailed technical explanation for leaf damage by this phenomenon in another thread as follows:

"This is FYI only and for those other forum members who might want to know some "WHY's" behind potential leaf damage............it is not just about AIR TEMPERATURE. It is also about wind, leaf temperature, and air humidity level. On a windy night with clear or cloudy skies LEAF temperature will be nearly the same as AIR temperature. However, on a cold, clear night with little to no air movement.....leaf temperature can easily drop 3 to 4 degrees lower than the ambient air temperature. (It can drop as much as 8 degrees in my area.) This is because of the radiation heat loss of the fig leaves. The rate of heat loss of those leaves is a function of the air's humidity level. At higher humidity levels often frost will form on those leaves. So, while the ambient AIR temperature might only be 35 degrees F......the actual LEAF temperature might well be 31 to 32 degrees F. That temperature could affect tender new growth.

In my area it is not uncommon for us to see frost form whenever the ambient air temperature is at 40 degrees F or below. This means that the actual leaf temperature reached 32 degrees F or below which froze the dew that condensed on the leaves as the dew point of the humid air was reached during the night. Late Spring frosts can kill fig trees in South Louisiana......especially if the outside air temperature has been cycling through several periods of warmth and cold. Yes, in my area, damaging frosts can form on fig leaves with ambient temperature as high as 40 degrees!! Ask me how I know and what I fear most at this time of year. It is really about leaf temperature and that is a bit harder to measure."

Dan

I thought I'd update on this issue. Temps fell to the low 20's last week, and my in-ground fig tree that had started breaking dormancy seems to have come out unscathed.

For future reference, what I ended up doing is...

1) place a 5-gallon jug of hot (i.e., boiled on the stove) under the tree. I placed this on top of insulation so that I didn't lose heat to the ground.

2) surround the base of the tree/water bottle zone with pink fiber insulation...I did this to have most of the heat go up and not out the sides.

3) covered the tree with a light insulation layer, basically an old mattress pad.

4) covered the whole deal with very large piece of heavy landscape plastic.

5) as a final barrier to any winds and to weigh down the plastic, I placed leaf-filled yard bags around the edge.

There were two days of sub-freezing temps. The day in between got up to the 40's, so I uncovered the tree in the late morning after it warmed up...of course, I repeated the covering again the next day.

This really was a simple operation, since I had all of the material left over from my winter insulation. The longest and most dangerous part of the project was boiling and pouring the water.

This was a very helpful thread. I appreciate all of the thoughtful comments.

Way to go
Sal

Geo,

You seems to have all the basics covered. Way to go.

Thanks for letting us know how you made out. Glad it worked out.