Please help, my bonsai is not okay!

[bosmixin]

Hello, for my 18th birthday my nana got me a bonsai so that i would have something sentimental to remember this moment and her by. Originally my bonsai grew very well and within a couple months it had grown exponentially, so i pruned it back to its original shape. Now, in late august, around 4 months after i got it in April, something has changed with the health of my bonsai, for the worse.

I have attached pictures of the before and after (they are taken outside for clarity but my bonsai is kept indoors) but are unsure how much you can see in them, so let me explain.

My bonsai is a Chinese sweet plum. The soil has started growing a layer of bluish whitish.. something that does not look to me like it is growing up the tree, apart from one patch at the base that looks like it has something powdery and white on it. The leaves started going yellow with darkish bits but this is happening less now with only a few at this time. They also dropped off frequently. As you can hopefully see in the pictures there are some healthy leaves but there is a larger number of green leaves that have paled a bit and curled and gone crispy.

I am thinking something along the lines of over watering but am unsure as to how this happened when i was very conscious of this could happen. In the beginning I watered a bit every day or so as the soil would dry out in that time, and what i read online and in books said that the soil should be kept damp. However now my bonsai can take up to a week to absorb the water it could before in a day or so, which makes my worried about damage to roots.

I live in England so the seasons have been warm, and getting warmer, so it couldn't be it doing something for winter.

Any ideas on whats wrong and how to fix it would be very much appreciated as this bonsai is important to me.

Thank you for reading I know i went on a bit.

 

[penumbra]

First thing, check the roots. That soil is pretty crusty looking. I would do a repot into a well draining bonsai mix for tropicals. Check the roots for any root rot evidenced by a foul smell or black roots that fall apart easily. Beyond that you need to assess your lighting and other growing conditions. While it is convalescing, put it outside in a bright but not all day sun.

 

[Tinyjames]

Yes Slip pot it in to a bigger pot. Have you done any research on your tree type do you water it every day?? is it out side all the time. it's not just the sun that will dry out the soil but the wind is a killer??

I'm a beginner my self so take my advice with a pinch of salt

 

[Shibui]

The white stuff growing on the soil is probably mineral deposit left from evaporating water. Mineral deposit is made worse by minimal watering. Good watering applies enough water so that water soaks through all the soil and runs out the holes in the bottom. That run out water takes away any leftover minerals so they don't accumulate in the pot. Minimal watering never flushes the soil so leftover minerals accumulate quicker.
Indoors we tend to not flush the soil because that can get messy but it is necessary. Maybe soak the pot in a tub when you need to water then leave it on the sink to drain before returning it to it's grow spot after the water stops dripping.
Adding more water on 1 day doesn't cause root rot. That's from adding more water too often before the soil dries. The wet/dry cycle is a good defence against root problems.
The mineral accumulation may be a reason for the tree not doing so well now.

There's a couple of reasons the soil could be drying slower now:
1. changing weather through the year affects how quick or slow the post dry.
2. trees use lots more water to fuel growth in spring and early summer. Later in the season growth slows and so does the tree's need for water.
3. Compromised roots can't absorb as much water so soil dries out slower.

Definitely check on the roots to see if you can spot any signs of compromised roots. The shape of that pot precludes simply tipping the rootball out to have a look so I'm not sure how you can check for healthy or diseased roots without repotting.
If there's any doubt you could do a quick repot to change the soil to something that drains better and holds more air. Repotting is not generally recommended for sick plants but if the soil is killing the tree then not repotting is a death sentence anyway. Indoor plant repotting times are way wider than outdoor bonsai and summer is actually the best time to repot tropicals like this one.
Don't just slip pot. That leaves the bad soil around the roots. Try to comb out a goodly amount of the old soil to get rid of the problems and replace with fresh bonsai type potting mix. Trim back roots if there's a lot in the pot but just comb out and repot if there's fewer roots.

Photos show the new shoots are very long and soft which usually indicates not enough light. That could be another reason for the decline. Leaves need good light to produce food. A tree can manage for some months but slowly starves without enough light. Where does it usually live? How much light? any direct sun through a window? Trees see light differently to us. What we perceive as a bright room is a dark cave to a tree. Middle of most rooms is likely to be way too dark for tree health.
Most indoor bonsai need extra lighting and indoor LED grow lights are one answer. Having the tree close to a large window is another possible solution.

Starvation from low nutrients is another possibility. Have you given it any fertilizer? Most bonsai growers tend to give the trees fertilizer every few weeks to maintain health. I would be addressing all other possibilities before rushing to fertilizer as too much fertilizer on sick trees does more harm than good.

 

[Tinyjames]

@Shibui I really like your answer to the above post 10/10

 

[ShimpakuBonsai]

The soil looks very dry and I think you should water more.
The white stuff could be lime build-up from regular tapwater.

Look at those care instructions:
- https://www.bonsaiempire.com/tree-species/sageretia-theezans
- https://bonsai4me.com/speciesguides/sageretia-theezans-chinese-bird-plum-bonsai/

 

[Michigan Tree Murderer]

@Shibui I really like your answer to the above post 10/10

@Shibui is awesome. He's a consistent wealth of knowledge, and super helpful. He should get a medal or something. I'd like to buy him dinner & drinks, as I've learned a lot from reading his posts.

 

[Wulfskaar]

@Shibui is awesome. He's a consistent wealth of knowledge, and super helpful. He should get a medal or something. I'd like to buy him dinner & drinks, as I've learned a lot from reading his posts.

I can definitely second that!