I'm sorry! There are so many possible causes for the dieback...lower light levels, too much watering, too little watering, disease....If you tell us more, we may be able to help you. For example, what medium do you have it planted in? How often do you water? What type of container is it in? How much light is it getting and what are the temps? I am no expert, but many here know lots and may be able to suggest some ideas for saving it.

How do you know you are not overwatering?

I took the plant completely out of the plastic (very large) pot and examined the roots. The medium had no compaction and was not wet....only slightly damp. Inside, I had been watering only when the top 3 inches felt dry. Maybe I was under watering...but still can't see how that had such a dramatic impact on the tree. There were a lot of roots that were yellowish tan and looked healthy. The roots still had plenty of room. If it were the medium I would think I would have seen stress on the plant prior to bringing it inside. The plant was growing new shoots and had blooms and some small oranges while outside. It was almost instantaneous that it started losing it's leaves once I brought it in. I have racked my brain trying to figure this out. I thought maybe the leaves would show some clues as to why it's dying (which is why I included photos). It was near a large window that received indirect sunlight while inside. Humidity inside is around 52% to 56% depending on the day. I have been so excited at the growth of this orange tree...it breaks my heart to watch it die. Since I made the original post I have taken the tree outside and cut all the dead limbs off and watered thoroughly and put it in a small greenhouse inside my barn directly in front of a south window. It gets direct sunlight now (filtered through the plastic greenhouse sheeting and glass window). It will get sun for most of the entire day....however the temperature will be colder than inside. I didn't feel like I had anything to lose at this point and couldn't possibly make things any worse for the tree. If you have any thoughts or advice, I would appreciate them. Thank you.

Has everyone checked their plants soil temperature, especially in the early morning when the sun comes up? It needs to be above 55°F for the roots to work. There are several posts on the forum that talk about leaf drop happening when the sun warms up the leaves and starts the photosynthesis process, but if the roots are dormant because the soil is below 55°F they can not send the water up to the leaves needed for the photosynthesis process and the leaf overheats and falls off from lack of water and nutrients getting to them. Maybe everyone should take readings of their soil temperatures and report here to see if this may be part of our problems. If the pot is on the floor, below the window sill, near a cool draft, etc, the soil can get quite cool, especially at night when there is no sunlight to warm the room and the heat is turned down. Under these conditions causing cooler soil the roots will go dormant. My pots are up on stands and above the greenhouse sides. I just checked several of my plants and the soil is in the mid 60s tonight, but it was mostly a sunny day which would have warmed up the soil. However, maybe the temperature is falling below 55°F on very cold nights, especially when there are many cloudy days in a row. I will start checking soil temperatures in the early morning again. I used to do that other years. It would be nice if we can figure out if soil temperature is causing some of our problems with our trees.

Cory

Thanks Cory....I thought that might be the problem but I have checked the soil temp. and it has been 60 degrees or warmer. Our home heat/air units is set on 69 degrees. I am sure now that I have moved the tree to my barn in a greenhouse the soil temp may be colder. So I am at a loss as to what to do.

Good point Cory. I check the air temp, but not soil. I don't have issues in the room that gets cooler though. Almost all of those pots are on rollers...not on the cold tile floor.

Yes....my pot was on a roller and above a basement. The floor temp would not be a factor for my situation. I used a long probe ( approx 5 inches) and stuck it down in the soil to check the temperature. It never showed below 60 degrres F.

Rdjacobs, as long as the sun is not warming up the leaves when the roots are cool, it should be ok. The tree will be semi-dormant at the lower root temperature and lower light condition. I wish you the best for your tree recovering in the spring.

Cory

Thanks Cory. What has scared me is not the leaves falling off (almost completely)...but rather the limbs turning brown (all the way to the trunk) and clearly dying. It seems that the condition is much worse than dormancy. Can it recover if ALL the limbs die back to the trunk?? Should I move it again?? If so, where??? It was not in direct sunlight at all where I had it inside. This is the craziest thing I have ever seen. All my other plants and trees I have moved inside are doing fine. I appreciate your input and wishes ;o) Renita