I am having roughly the same problem. I've seen one or two scale, and am having the unexplained leaf loss, leaf yellowing (though some are also splotched with brown), and dieback. It has killed a few trees that I, like you, have indoors (I'm in 7b). I hope someone can provide an answer, as my regimen of Safer soap and copper fungicide hasn't been too successful.

WLD + N deficiency and maybe a little root rot. Starting with the leaves, the fact you have not fertilized at all in the winter is probably the cause of the vein yellowing showing up as N deficiency then dropping. The twig die back is normally caused by root rot or root damage. In your case probably root rot because of over saturation and wet cold root area. Let it dry out more and or heat the root zone to above 55F. you may have a little WLD happening too mixed with the N deficiency not sure. Winter Leaf Drop occurs when the tree receives too much light and the root area is too cold (below 54f).

To go along with Ryan's kind help, your mix plays an important role as to whether your tree can handle a good watering in very cool temps and low amounts of light. You have to water no matter what once the soil has dried out.

So don't let the cold, lack of sunlight or an inappropiate mix hold you or your tree captive.

Hopefully, you will address the watering/mix issues before you even consider correcting anything else since nothing is going to fix the nutrient issues permemantly until the roots are in good health.

Good luck

Mike:-)

Thanks for the advice folks. I will be attending to its needs on my day off. I am planning on de-potting to check the roots out and give new well draining organic soil (Fox Farm Ocean Forest). Then water thoroughly with distilled water plus a light fertilizer application.

Ryan, what is a WLD deficiency?

Do you think that the tree was fine in the grow tent with the light and it was just the nute and soil issue? Could it be returned to the tent after treatment, or would it be better with a few hrs of real sun a day with a supplemental grow light? Just 2 months ago it was flowering and fruiting like crazy in the tent - I wish I would have known all this back then.

Thank you again.

To follow up - I am most concerned that branches are dying back. This happened 3 winters ago and the tree lost all but two branches and all but 3 leaves. It made a full recovery in the spring/summer, but I feel that it set the tree back a lot. I would prefer that not happen again. I will do anything so no more branches die.

Garret, the mix you speak of using is not appropiate for your tree if it is the one that I think it is that holds water far too long and break down only after a few weeks.. I have used it and killed a many plants with it, especially citrus.

Just a heads up.

I would use a mix that contains very few fine particles and that is very porous.
Even one part of that mix to 2- 5 parts of perlite would be better. You know your area more than any of us and you would be able to judge whether your mix is drying out in a timely manner and whether or not that same mix is allowing the roots to breathe by good gas exchange every time you water.
One that allows you to water more frequently without fear of root rot and salt deposit build up which is likely the demise of your tree. The root rot caused from too much moisture for too long and the salt deposits that is.

A mix that will not compact and suffocate your roots causing you to have to start all over again and possibly loose another tree.

Right now, your tree is VERY weak.

You take your chance in using a wick in the hopes of that your mix will drain better and dry out more rapidly.

OR, you can always risk repotting it, sort of a 911 thing and hope it perks up right away and that it does not shock your tree after what it's going through. I mean a full bareroot into a much better mix.

You live down south like that? You have the advantage of much nicer weather and warmer days than me. Your sun also works much harder than mine.

Why would you need supplemental lighting?
Your sunny days in that tent, which I assume is very bright should be sufficient enough.

Mike:-)

This post was edited by meyermike_1micha on Wed, Jan 16, 13 at 15:49

Mike - Thanks for the heads up on the soil. Can you recommend a good brand, or would it be easier to buy some perlite and mix it in? I have a moister meter and it seems like the bottom of the pot is always wet, while the top is always bone dry. I think I should re-pot it into a new container as well.

Also, even though I am in Zone 6 we have very overcast days in the winter. To make the light matter worse - I live in a city and the building next to mine blocks a majority of the sun in winter. Thus I could not grow citrus without some kind of grow light. Summer time is no issue because of the angle of the sun.

Ryan - Good advice, I am going to combine your 3 point plan with what mike previously said. I have much more hope for my tree now. Although I wanted to take action on this today, I cannot because I need more supplies from the store. Poor tree will have to hold on another couple days!

I know a good professional SOILLES mix will do you wonders.
The key is to get one with bark as a majority of the mix and not peat or fine particles.
Or, you could use a small amount of what you have access to with lots of perlite.
There is also 'Fafard' mix.
Then there is also making your own with bark fines, perlite, and a tiny bit of peat.
You have many options.

The key is to make sure it's fast draining and porous and you could do this as long as you understand the concept behind these types of mixes.

Ryan also has a good plan. That extra light and warmer temps will encourage your tree to drink much more efficiently and encourage root repair as it tries to grow at this time instead of waiting for longer sunnier days to encourage it..

You also have the option of using a wick. Have you considered this too?

Also, use a wooden dowel or bamboo skewer to test for moisture.They are much more accurate than a moisture meter if pushed right into the root zone to the bottom where believe it or not, many roots are if they are still alive.

Anytime. We are here for you.

Mike

I had to put the tree back into the grow tent today. The last few days have been very overcast and dark. It would get much more photosynthesis done under the grow light.

Since it will be a few days till I get supplies, should I give the tree a watering with fertilizer? I cant believe I didn't give it any nutes all winter. For some reason I thought that I shouldn't fertilize it this time of year.

Another update: Even though there is some twig/branch dieback, there are many tiny new branches sprouting out.

This has all been a great learning experience for me. Years of caring for this tree has taught me a bit about citrus. Is there ever gonna be a year where I get everything right? Or are they naturally fussy? I am trying to learn exactly how to care for them throughout the year (as different seasons mean different treatments) so that someday it will just be natural. Is that possible to achieve?

UPDATE: I repotted the meyer lemon into a new container with a new soil mix. The container has a 12in diameter and about 18in deep. It is plastic (clay colored) and has a good amount of drainage holes. The soil mix I created was roughly half Fox Farm Ocean Forest and half perlite. I also purchased an organic citrus fertilizer that I mixed into the soil at the recommended dosage.

When I examined its root ball I was shocked to see that it was completely bone dry (it has been getting watered regularly and the moisture meter always said it was very WET towards the bottom), also no rot or mold either. I was for sure that the roots were rotting, but I was wrong.

Could that be a cause of this die back? That the roots were bone dry for long periods of time when I thought it was wet?

I am also starting a new regiment where I will leave the tree in front of the window for the few hours of direct sun, then move it into the grow tent for the rest of the day.

Next I will get gardening sheers and neatly cut off the dead branches. Hopefully in the next few weeks I can report strong growth. Updated pic below.

{{gwi:559925}}
^Finished Product^

{{gwi:559926}}
^New Soil Mix^

Are you kidding Garret? Learning will never stop, even with citrus trees. I think many here, even the experts are always thrown a learning curve.

I guess the challenge of growing these trees is what makes many addicted, well in my case. It's like growing grass, it's not easy to keep a very green lawn going every year, but I don't want to live with a dirt yard. The reward of a full green lawn at the end of summer is my goal and reward! The same with citrus, if I can get all their needs right, they will reward me.

Is that a south facing window? If so, the why are you moving it? Caring for your tree should be a lot easier than you think if you have given it good mix, a light amount of fertilizer at each watering, and a nice sunny spot.

Every time your root ball dries like that, you kill off the fine roots that do all the bull work of drinking and feeding. Yes, that can cause branch die back even though you think the larger support roots that hold onto the soil look good. It's the fine roots that you never notice that die, especially in the heart of the root mass.

Mike

This is my Meyer lemon,while in greenhouse was doing quite well. Brought it in,my water and pH meter said it was wet. So transplanted it,oh is good. My meter keeps saying it is dark even with grow light. What should I try