Help invigorating a tree after leaf loss [pics]

[turkeydinner]

Hello.

I have a bonsai(Edit/Add: Fukien) that was gifted to me 1,5 years ago(last early autumn). So it has a lot of sentimental value to me and I am really trying to pay it much needed attention.
It was doing fine the last winter and this summer being constantly fully in leaves, occasionally flowering(never fruiting) and doing well overall. This early winter(~2 months ago) its leaves
started to turn brown/black and die. I was worried, but reassured myself by reading online that
they are picky trees and will drop all their leaves when in stress. I guess it may have stressed
about central heating being turned on and the little light it received in its past position.

It was in my bedroom and wasn't under my constant supervision so while it was dropping leaves I moved it to my living room. It still continued to drop leaves and was finally basically bare - only a couple of leaves here and there. And many turned black and died as soon as they formed.
The tree went from fine to horrible in about 2 weeks.

This got me worried for all sorts of reasons - root rot, little light, over/under watering, climate change, disliking my girlfriendP), etc. But I had faith in my tree.

So, then for some time I accidentally kept it near my central heater(because it was near the window and in a visible space for me) and there the tree started to recover from the fast-loss-of-leaves but still visibly struggled.
There were some leaves, and it seemed the tree was finally able to hold on to most of them.
The last step was the lighting - I moved It farther away from the heater and bought it a LED(2R+1B/6W) grow light which I keep about 30 cm above my tree ~18h/day.

Immediately after that I noticed the tree stopping leaf-dropping immediately and started developing new leaves. So by now I have two problems:
1) Many of the leaves have grown _huge_ by being under lighting for 2 weeks - the biggest leaves are a matchbox length(from tip to end of leafstem) and over half as wide.
2) The main problem is that the recovering foliage is rather thin. And there seem to be places where the foliage is not growing at all. Before all this the tree had dense and even covering (it had 3 main "pillows" of leaves covering the tree).

The huge leaves I can at least partially attribute to the extremely better conditions(light, no central heating) it has now. But the uneven growth is what gets me worried. I did the scratch test on some of the bare branches and although I noticed that at least one _might_ be dead, the other ones were nice and green under the bark.

So I guess my main question is... how do I encourage new leaf formation in other places on the tree while also getting the leaf size smaller without stressing the tree much?

My own thoughts: Trimming some of the leaves(cutting them in half maybe?) is probably one of the ways? But it is winter, and the tree was just under a lot of stress. Should I do something now? Wait several more weeks/months? Is there _anything_ I should do now to make the tree more happy and at the same time still encourage some new growth?

I am certainly planning on repotting the bonsai in the spring, because It seems the soil is keeping water much too long. But I took a photo of the roots, and they seem a bit weird on the photo, but to the naked eye they seem not too bad(compared to other "fine" photos on the net). It is still in the pot/soil that it came with.

Background: I have had a few fukiens in the past and have read extensively on the subject(probably not remembering much of it though ). Also have been a forum lurker for years, but now I am worrying and in trouble, so every bit of help is very welcome and appreciated. I couldn't find a definite answer to my problem on the Internet.

Also any other tips and comments are welcome.

Thanks!

PS! Sorry for the blurry images. If you need/want clearer pictures let me known.

 

[thumblessprimate1]

Where are you located? I'd just let it grow to improve it's health after what it's been through.

 

[turkeydinner]

I am in zone 5(bordering 6). And more precisely - Estonia. Although I could leave it outdoors in the summer, I have kept it indoors the whole time.

 

[Poink88]

Welcome to B-Nut!

Now is not the time to worry about the leaf size. Leave it be and let it recover...do not even prune it. In a few months you will know whether the other branches are dead. Repotting season is coming, your fukien tea looks it need one badly.

Looks like you did your homework. You are good to be able to make it survive indoors this long so you must be doing something right. I am not sure mine would survive that long indoors.

 

[turkeydinner]

Thank you. This is what I was basically hoping to hear.
I am going to give it more time to refoliate/restore and make the big decisions later.

 

[Poink88]

Note that had the tree been healthy...you can technically repot anytime since it is protected from freeze and it is broadleaf evergreen. BUT it really need to recover so wait... unless the soil is causing the problem (root rot for example).

 

[turkeydinner]

Thank you for you answer Poink88!

I was thinking about my tree today and I have a feeling I need to repot it soon, since I suspect it is very rootbound, the soil is very compacted and moisture holding(I water it about once a week - bad, I know...but it has endured it this far) and I have a slight fear of root rot. I have one of those "easy grow" pots that lets water run out of the bottom into a bottom container and then it acts as a humidifier.
So, I looked out myself a seemingly suitable mix of one of the few locally available soils (60% akadama, 30% peat moss, 10% kanuma). Googling didn't indicate anything inherently wrong with this mix, although several sources said 50/50 is the best for FT and others said 90/10. So I believe I am in the golden middle.

So is there anything wrong with my idea? I really want to repot it ASAP, although I would not want to cause any more harm to it.

So as Poink88 said, I should wait and see what happens...how long should I wait and what should I look out for? My prediction is that it is going to stay somewhat the same(big leaves, some empty branches) and continue some growth for some time. What is the correct tree-is-fine-repot-now signal or point in time in this case?

As always, all answers are highly appreciated and truly make my day (and my trees)

 

[Poink88]

I've given you enough scenarios when to choose one over the other...you alone can tell which action (or inaction) is best for your tree now. Sorry.

In my mind, since the tree is improving recently, just do what you have been doing until the tree recovered for at least 6 months. That is what I would do if this is my tree.

Re: soil mix...that is highly debatable. Know this, plants roots need water but also need to "breathe". Plants in nature grow in rocks, soil, clay, etc. so they can survive a wide range of substrate. Which is optimal depends on you...how you care/water your tree, the environment you put it in, etc.

Good luck!