I was recently given this beautiful bonsai and I water until the soil is moist nearly every day. But recently it has started dropping leaves and these little white dots are appearing. Why is this happening and what can I do? This was given to me for my birthday (25th August ) but this has only just started to happen. Any help is appreciated! Thanks
This is an elm bonsai and as mentioned in an answer I provided to another question now is the time of year when elm trees drop all of their leaves because they are deciduous. So this is normal for this time of year and expect your plant to have no leaves by the end of Fall / Autumn.
There may be another problem here if you are keeping the plant indoors all the time and watering heavily. I'm not sure if the white is bugs or mildew, but either way, if you are keeping the plant indoors and there is too much moisture you are going to have problems.
If you are keeping it indoors, it belongs outdoors. In the case where you have serious amounts of snow during winter you can keep it inside a box with a glass lid to winter the plant. If you are already keeping it outdoors, I suggest you review my other question about watering routine. Don't forget your plant needs occasional watering even when dormant.
If you are getting mildew, mold or bugs I suggest you clear the leaves around the base of the tree which can provide a place for any of the above to hide. Especially at this time of year when your leaves are going to be falling.
Personally, regardless of what the problem is I would be preparing the plant for winter because you are going to lose all of the leaves anyway. Make sure your plant is outdoors in an area where it won't be sitting in heavy snow and clean all of the leaves and other stuff away from the base. Keeping the plant clean is key to it not being reinfected when new growth comes back in Spring.
Also, quarantine the plant. Don't sit it next to other plants that are going to pass this around and when cleaning the leaves dispose of them in a garbage bin rather than sweep them off into an area where this could spread to other plants.