What kind of low temperatures are you getting right now? It needs to be outside if you are not having temperatures close to freezing. That will cure you leaf drop. Also your lemons are ripe. I dont know what kind it is or if they hold well on the tree but with just a few and that tree being smaller and having trouble I would remove them. Mike

Hi all, I am new to this forum, I have read this thread, but would like to double check my information to make certain my little lemon tree is doing okay. Briefly: I purchased the tree in the spring of 2011. I live north of Chicago. The tree spent the spring, summer and autumn on my side deck with a southern exposure;I have many mature trees (50+ years), and this area gets the most sunlight. The tree seemed to do fine while outside, I brought it inside before the frost. My house has floor-to-ceiling windows, so I placed the tree in the same exposure, except indoors. It probably receives strong sunlight probably 8 hours per day on sunny days. Today is 21 January, and recently just about all of the tree's leaves began to shrivel. They did not turn yellow, but they did die (become crunchy) and began to fall off. I was very alarmed, but after reading this thread, I believe the issue may be that the soil/roots were cold. I do not presently have a thermometer (it is after 1 am and we just had 9' of snow!) but the container does feel quite cool. The tree has never had any fruit, just one marble sized green lemon that I have not removed and some white buds, which I have also not removed. Here are my questions: 1) It appears the tree will lose all of its leaves, but that does not mean the tree is in danger of dying, correct? 2) If I am to understand the problem with the contrast of sunny leaves/cooler soil/roots, this problem can be rectified by either keeping the tree in the sunlight and warming the soil (with xmas lights, for example), or by moving the tree out of the bright sunlight so it can "wait" until going back outside in the spring. So, I can move the tree to a less sunny location and it will be fine until the spring, given all other things remain the same? I should add that I take pains not to overwater, and the room where the tree is located is quite dry with little humidity. I have used good soil and, as a bonus, since I have pigeons, I have also used some of the pigeon droppings into the soil. I have done this with great success with my other plants and in my garden, and with this tree during the warmer months when it was outside. Thanks in advance for answering my questions, I really appreciate it. I just want the tree to be happy and to be able to overwinter indoors with as little stress as possible. Thanks again, Bill B.

Thanks tigereye. I washed the foliage down and rinsed most of the soil from the root ball and trimmed the roots down so that it all could make contact with the new mix, then watered the mix. Right now it looks good, just hope that it is happy and thrives. Thank goodness I bought a pot last year in anticipation of putting it in a lighter pot to make it easier to move in and out for winter and spring. Thanks again for your responses.

Here's a good link on soils for citrus trees. There's also a decent discussion by Al on here of soils, but I don't have that link. https://www.fourwindsgrowers.com/blogs/four-winds-growing/soil-mix. Four winds also has some other good information for growing citrus indoors. I prefer mixes that have pumice in place of pearlite and recycled forest products in place of the peat as they seem to do better for trees and other plants, but it's really personal preference. If you can, I would allow for a temperature drop at night for the trees, citrus tend to like a temperature drop of about 10 degrees at night. Indoors I would also get an oversized drip tray, fill it with lava rock or other large rock (this is decorative, so it really depends on your style, what you want is rocks large enough to allow all the water from watering to drain into the bottom tray without touching the bottom of your pot, so that the water doesn't reabsorb into the soil. You could also use pot feet inside the tray and it would do the same thing). What this does is it allows for an increase in humidity around the tree as the water evaporates without needing to use a humidifier. It can really help to have. And when I say oversize, I mean for a 14 inch pot you want at least a 20 inch tray. For my big citrus I use steel trays on rubber castors, for my smaller ones I just use the standard vinyl drip trays. A bigger tray also works well, if your tree does well, catching the occasional leaf and spent flowers so they don't wind up on your floor.