When you say "perform" do you really mean "not die"?

I have found that it's not so much temperature but LOW HUMIDITY that is the cause of citrus dying indoors. A cool garage (45-50 F) will keep citrus dormant and when you bring them out in the spring to enjoy some nice weather they respond by bursting into blooms.

Light is good but it's the dry air coming from the furnace that roasts them and causes leaf loss. A key lime I had in my kitchen suffered terribly. A lemon and grapefruit in my garage barely lost a leaf all winter.

COOL (not FREEZING) is just fine. They won't grow at all but they'll be OK. Unless you feel up to humidifying your house in the winter up to a high level, you're going to dry them out.

In the main California citrus areas Dec and Jan temperatures ave about mid 50s highs and mid/upper 30s lows. I keep to the same range in my greenhouse. The fruit of pummelos and Washington navel ripen to high quality during these temperatures. I keep the humidity as low as possible but it's not too low. I don't think that spider mites would be much of a problem at these temperatures but I do need to spray once a yr.

If you maintained these temp for 6 months that might be another story. But it obviously works pretty cold for a couple months.

The Fruitnut

I use this room constantly though..The coldest I can keep it at night is in the 50's or 60's since that is where my tv is. It is a room in my home. Not a detached room or greenhouse. It is the only room of the home that gets all the south facing sunlight...
Will they be ok at these temps? And do I still need grow lights at these temps? Or will they respond badly?
Every year before this winter I wa sgiving them over 8 hours of growlights and sun, along with very warm temps which seemed to mix well except for my meyers...Then came all the mites and pest problems..

Mike, I've no experience with overwintering indoors, but like va_canuck and fruitnut said, the temps should be fine. If the humidity was not a problem before, at higher temps, it should not be a problem when cooler.

I don't think you should need extra lighting if the room has south-facing windows. Just my opinion, though.

I'm having an indoor-move related problem with my variegated pink lemon tree. To start, this past July I moved from the Orlando, FL area to upstate NY. The tree survived well, with only minor visible signs of stress (a few leaves turned yellow and dropped). When I got into my new place I put the tree next to the window (all windows face west in my apt) with a grow light to make up for the differences. Starting about a week ago, leaves started dropping daily. I'd say probably 30-40% of the leaves are gone. Some yellow then fall, others fall off bright green. Any ideas on how to stop this?

I water only when needed and am using a 20-20-20 fertilizer at the suggestion of the local nursery (2x/month). I've also sprayed twice with an organic insecticidal soap to kill off any buggies. (lots of spiders in my apt)

I'm posting this here, but if anyone feels that it should be moved, free.

You might consider posting your own message, to insure that you get full attention to your situation (as opposed to piggy-backing on Mike's post.)

I know that Mike won't mind, so I'll make a comment or two.

I suspect that your plant is showing signs of a change in climate, sunlight, etc. Most plants undergo acclimation by doing whatever they need to in order to survive. Shedding leaves would be typical, if a plant is moved from a high light situation to apartment living.

I do think that the twice monthly fertilizing may cause problems, unless your soil is extremely porous and fast-draining. Which I doubt it is. Hold back on the fertilization, especially since your tree is undergoing stress at this time.

Be prepared to reduce watering as the fall and winter settle in, as well.

Bright light and warmer temperatures will actually compound any problems associated with low humidity. If you can be fairly vigilant about misting the tree down on a consistent basis that will surely help, but it's still going to not be happy. Make sure any heating vents around the plant are closed, as warm dry "wind" will be quickly lethal.

If you have the capability to put a humidifier in the room - even one of those Vicks vaporizors, that will definitely help. Your windows may crud up with condensation though - careful.

The happiest tropicals indoors have always been ones kept in our bathroom. The humidity from the showers and such....

What va_canuck said! Also, on the low humidity front... air conditioning is bad news. Keep it away from your tree.

How to keep the tree from frying in the summer afternoon west sun, now that is another problem, sigh. Indoor growing is quite a challenge.

Thanks for the help everyone! We have central AC, so the vent isn't aimed anywhere near my tree. Back in late April I repotted with a 50/50 mix of perlite and potting mix, so the soil drains quite well (lots of new growth afterward). I'll cut back on the fertilizer and see how that goes as well as picking up a mister bottle.

Thanks so much everyone....The one thing I forget to detail was that yes, I do have humidity issues, in the sense that I have to use a humidifyer everyday when the heat is on, especially if it gets warm in that room..I even use water fountains..Sort of like a tropical oasis. I always keep it the warmest room in house with high humidity..I forget the humidity one day, boy do the plants rebel!!

The things is, even when I use the humidifyer 24 hours a day, I still have to keep up with the pests..I keep the room at 70 or more percent humidity level. The windows do muck up. But the bugs still come if I don't spray on a regular basis...

Every plant seems to love this enviroment except my meyer lemones...They are so stubborn.
The leaves drop no matter what I do..But I have not tried the colder enviroment yet..
Funny thing is, when I brought 2 of them dying to work, where the temps stay cool, the air dry, and lots of sun, they came back, but still had to keep up with mites.

This would be the first time I try a radical move from warm humid conditions all winter, to much cooler conditions, maybe without a humidifier. I guess I am a little scared you could say.....I was hoping some one would say exactly what I had to do to make it work.If it is possible to keep healthy citrus all winter like this..

Therefore the question...Less light if cooler conditions? Not as cold as some suggest though, like a garage..My garage can be below zero and has no light at all. I mean no grow lights, are just south facing windows good enough? Do you think my trees will be ok if I grow all winter at much cooler conditions like the temps I mentioned above, and less light?....I know the pests will certainly be minimal...This is my goal...Less pests, a lower electric bill, less worry about humidity, less leaf drop, probably less new growth too, what the mite seems to hit every year, they don't eat any old growth...

I remember last winter when that room accidently reached over 80 degrees because my niece raised the thermostat, all the lemon meyer trees lost their leaves within days, and a couple died..Anyone confused yet? Lol

I will re-read these posts and see if anyone has hit it on the head about my dilema. Been weary lately...t tired to think..sorry

By the way, no worries about piggy backing, it can be a fun ride..

Anytime rhizzo posts, it is great to see what she has to say..:-)....Everyone else included...

I will be quite embarrssed if anyone here has already gave me the answer I needed..

If you spray the trees with oil a couple weeks in a row before you bring them it will seriously put a damper on the mites. I spray my two trees twice and usually never have a problem. I'm in zone 8 so that seems to take care of it- you would likely have to spray again sometime during the winter. I don't know where you could spray in the house though- oil sure is messy but non-toxic at least. Maybe the shower if they will fit?
Cool temps are best- sometimes when we are expecting mild temps in the 40's at night and 50's day I will put them out on the deck and just leave them- they seem to do very well. I have very little light in my house so I think they do better outside, short of frost/freezes, than inside.

I forgot to add- has anyone ever sprayed with Wilt-pruf? It seems that would help with the dry air and probably stop most of the mites too I would think. I'm thinking it would last most of the winter inside since it was designed for outdoors after all. As far as I know it is non-toxic too. Just a thought... Frank

Frank, that Wilt-pruf idea is a good one. I'm assuming it is like Cloud Cover, which I have used in the summer if I'm going to be away on vacation (to keep my Japanese maple from wilting in the dry heat). I'm not sure about its effect on mites, though.

It's water-soluble out of the bottle so you could re-spray in the shower and just rinse it off the walls.

I get it.....

Cool temps with less light should be ok...

It isn't the humidity I was so concerned about. It was a cooler temp verses how much light that was.... I will just let the south sun only take care of the light, and much cooler temps... Let"s see what happens..I will post a follow up...Thanks so much for all your help. Great suggestions!