Hey there!
I got my first ever Zelkova Bonsai this summer and he's been doing really well. However, the soil seems to be sort of moldy and it's losing quite a lot of leaves, which also look slightly flaky. It's sprouting new branches and lots of new flowers, but the flowers aren't really opening up like they did in the summer. I heard to check the roots, so I had a look at the roots visible above the soil and these very thin roots broke off easily. The thicker ones are strong.

I've added a picture of the soil and of the bonsai itself so you get a general idea of what it looks like.

I fertilise it once every one to two weeks and I had it on my windowsill (where it gets full sun in the mornings). It seemed to be happier now I moved it out of the full sun during the day and cold window at night so it had a more constant temperature.

I really love my bonsai and would hate for it to die! Are these signs of it being unhealthy? If so, what should I do?

Thanks so much!

Quick edit: As you can see on the last photo the sprouting flowers haven't opened up entirely, but are dead, while the other buds are still green.

Medomai wrote:

I got my first ever Zelkova Bonsai

That's not a Zelkova but a Carmona.

Are you certain? My Bonsai came with a leaflet stating it was a Zelkova.

Auk beat me to it, it is a Carmona, and the soil looks poor. It is an a very small pot too, I think you need to re pot soon, stop the fertiliser, and keep it out of draughts. It is not a hardy species so will have to be protected from frost. Don't put it in a window with a heat source under. The loss of leaves is a bit of a worry, could be due to a number of things, but I think the soil could be the main problem. You need to say how and when you are watering, you must do this properly. Allow the soil to almost dry between watering soak the soil until the water runs out the bottom of the pot. take a look at bonsai4me.com for species guides.
Geoff.

Thank you so much.

In the beginning I used to water it, like you said until water came out of the bottom of the pot, pretty much every day, seeing as the soil would be dry after a little more than 24 hours.

I was afraid the 'mold' (if it is mold) was appearing on the soil because it stayed wet for too long. I watered it two days ago and the soil is still pretty wet.

This is the pot it came in in the shop and they instructed me to only repot it in two years or so. Do you advise me to buy a slightly larger pot and new soil?

Thanks a lot!

You can get a larger pot, as m5eaygeoof said. Definitely change the soil to a more aerative kind and free draing kind like akadama. The mould is most likely moss so you can keep it for the next repot or just pinch it off the soil.

Temp:12-22 ' C
Pruning:anytime
Wiring:anytime in growing season
Repot: every 2-3 years
Watering: general watering practices.
Feeding: feed with any fertiliser that has a good npk value and feed when it says on the packaging.
Position: bright but not direct.
Humidity: does not like really dry conditions

Medomai wrote:

This is the pot it came in in the shop and they instructed me to only repot it in two years or so.

They told you it was a Zelkova too...
These mass products are sold by people that have no knowledge of bonsai. Better trust the advise you get here, rather then what they told you.

Medomai. Dont get us started about mallsai!

Haha! I realise you guys know your bonsais! Thanks so much for the tips. I'm ordering a new pot and some soil now. Would Akadama soil be the best kind?

Well, it would it would certainly be the best for now. As the years go by and you gain more experience you will start to find the best soil mix that suits you and mix your own soil.