How cold are your freezes, and how long do they last?

Do you mean those butane ones, or those disposable gel packs/infant heel warmers? And I assume you'd cover the tree as well, to trap the heat?

I've used Christmas light strands to provide extra heat, so that is an easy option for a light frost--those tube-style ones can put out a decent amount of heat and they are easy to work with since they are smooth.

Thanks for your response.

I mean those cheap, disposable ones you keep in your pocket for camping, etc.

Freezes never last past 10 am or so the next day, and it rarely drops below 30.

Yes, I took a huge piece of lattice work that I bent and tied together to make a huge cylinder and was planning on covering the tree with that and a tarp or blankets over it.

Is it more important to keep the roots and trunk warm, or to keep the leaves covered (or all of the above)?

Christmas lights does seem a lot less hassle, since you could just leave them on all winter and plug them in on nights that it is supposed to get cold. Do you still cover with the lights?

You won't need to worry about the roots at those temps. You may wish to cover the tree when you do need to apply an external heat source, especially since your tree is very young still--it's all about surrounding the tree with enough heat to keep the frost off. I think that Moros are kinda cold-sensitive and so I think you are doing the right thing to be prepared for colder temps. Be aware though, that the tube-style lights generate quite a bit of heat ( and light! the clear ones are *bright*) and so you may want to monitor it carefully till you are familiar with them. I used them to wrap around containers for root temperature manipulation--works pretty well, though with my containers lined up like they were and lit up, I ran the risk of planes trying to land in my garden :) I am sure the neighbors think I am a nut.

Since heat rises, you can concentrate some of the light strands a bit lower on the tree, and that should help make sure that the heat is evenly covering your tree. With a cover you should be all right. In the past, with frost-sensitive plants, I have used wire cages made out of strips of fencing wire (that stuff that is not-quite-chicken wire that comes in rolls) fastened into a cylinder and then put just a big plastic bag over it (I refuse to do this anymore--getting lazier as I go :)

HTH.

Iv'e a question about watering plants when there Christmas lights are used. Doesn't water hit the light? If so, isn't there a chance of getting electrocuted? I wouldn't mind using these lights on my citrus, but am scared it'll shock me. Can this happen? Toni

Of course you could get electrocuted. Anything can happen. A plane really *could* try to land in my backyard but that is a risk I am willing to take in my experiments with citrus ;)

Doesn't anyone in your neighborhood decorate the outside of their homes with outdoor-rated light strands for the holidays, Toni? Surely you must know what I am referring to. And how exactly do you water your plants so that lights in the canopy of a tree get wet? Of course, you'd want to use caution when dealing with electrical wires--like, maybe not spray them with stuff like fish emulsion; ciggie wash; Superthrive; decoction of Eye of Newt, Toadstool, & Batwing; Everclear; or even water if you can avoid it.

Teasing you of course, Toni :)

LOL Rick, didn't you know Eye of Newt benefits citrus? LOL j/k..
I wouldn't mind using lights for plants in the gh which gets pretty cold in mid winter, but don't want to get shocked when watering plants..Especially if lights are set in soil..
Is placing in soil the intention of keeping roots warm? Does it really work? I'd have to go out and buy several sets of lights for my trees. Also, are they supposed to be left on 24/7? But, I have to do something soon, like yesterday, since the temps have gradually been decreasing. We've had a few 40 degree nights already, and my citrus are all outside.
Gee, hope there's no planes in the back yard..lol..Toni

I'm Jewish so I don't know squat about Christmas lights. Are there different kinds for using indoors vs outside? The ones that people use to decorate their yards and home exteriors have to be weather proof so I wouldn't worry about getting them wet.
Karyn

"Weatherproof" only means that it is safe to use outside on a normal weather raining or not. It is not submersible. When you water your plant and and if your lights is atop of the pot soil, some of the lights maybe submerged in the water. That's when it is not safe. Electricity is something you don't take for granted. It will travel on anything wet (except on pure distilled water). Always take precaution. Having said that, since Christmas lights as some of them are connected in 'series', there is a comparatively low voltage drop per light. You will not get the full 120 volts in your body. But you will still feel the tingle.
I put my clear Christmas lights around the outside of the pot to warm the soil and around the leaves' perimeter but mostly just under the lowest branch since heat rises if I want to protect the leaves at night during very cold temperature with clear plastic on top of the canopy.
I've been doing this for 4 years now and saving my plants each year from frost burn.
Note: My experience tells me that I don't believe so much with manufacturer's sign as " weatherproof". specially if the product is not made in US. I got burned so many times but where to complain I don't know.

Toni, I don't know where you got the idea I place the lights in or on the soil. You may wish to read a little more carefully.

Rick, I didn't mean you specifically..It was an open question, meaming anyone using Christmas lights on/in the soil.
The idea of using lights where water is going to be applied frightens me; I don't like messing w/electric, period.

Karyn, there are indoor and outdoor lights. When I decorate outside, I use a plastic bag on the timer in case it rains/snows. I still don't know how safe it is considering the bulbs are sitting out where moisture can set in the bulbs.
Since we've had major rain storms in Aug/Sept and now Oct, it finally happened..Our basement flooded..over 3' of water..pots were floating like mini boats..it was terrible. And again today we had more rain..will it ever end?? Some parts of the coutnry are as dry as a desert, while other states are getting loads of rain. I still have plants to haul inside, but don't want to work in the mud. One advantage is, it's been in the 80s the last couple days..but it's so humid nothing's drying. There's nothing but mud out there..
I don't feel a need to set lights indoors, but wouldn't mind setting something up in the gh where it gets cold in winter. And I've two heating units..gas and electric. Plus I keep a fan going to circulate air. I'd have to purchase all new (clear) bulbs first, since my sets are multi-colored. I think clear is best, does anyone know? Toni

Hi John. I live in northern San Antonio and I have Ruby red grapefruit, Washington navel in the ground. I have a Moro, 2 lime, 2 lemonquats, meyer's lemon in planters. All about 5 years old and doing well. When I first planted my citrus trees in the ground I built plastic PVC pipe frames and covered them with clear plastic which I bought at HomeD. I built them large enough to keep my potted citrus, which were tiny then, protected from the cold. I used 100w-250w halogen lights for warmth. I also bought outdoor thermometers to check them temps in my back yard and kept close tabs on the weather. My neighbors thought I was a "nut" but every dec they are waiting for their samples. All of the trees in the ground have grown so large that I have'nt protected them for the past 3 years. Good luck.

Annd that's what Menlo Growers does to their citrus in Winter time.
-Putting up clear plastics with PVC frames for their thousands of citrus in pots. It shaped like a half round igloo house. And they remove them come Spring time.
I dd not see any light bulbs built for warmth.

All of the above posts notwithstanding, if keeping the roots and lower trunk warm is the issue and frosts are never severe, then laying a carpet of straw around the base of the tree will work too. More organic / eco-friendly too!