chinese elm bonsai

[claire]

I have a chinese elm bonsai about 7 years old, which is looking a little unhappy! its leaves are not shiny and green but dry and some are yellowy others are brown at the tip and along the top edges. I am very concerned that I am doing something wrong and its going to die! I have been watering it little and fairly frequently and it is growning some moss now on the top of the pot is this ok? When should I be feeding it and how much? also I read that the brown tips come from salty water but I have only used tap water to water it..do you know what could be causing this? and what I should do?

[The Helpful Gardener]

Water is always the best place to start when looking at bonsai problems. You said tap water: do you have city water? If so, the chlorine can be an issue, especially after a long period. Let's not forget that's a poisonous substance and none of us would do well with regular dosages of poison, no matter how small.

Try leaving tap water out to sit in an open (read bucket) container to degass for at least 12 hours; 24 is better. Use this water for your watering (I found when I was keeping aquariums that it was a great way to change out water by simply using the aquarium water for bonsai and replenishing the aquarium, but I wasn't using city water either; you have to treat tap water for fish , too. You also say you water little and frequently. Try dunking that pot in the bucket once a week in growing season, maybe once a month in winter. There is an old saying about wwatering oncce for the pot, once for the soil and once for the tree. A little drink here and there may be getting the first two and not the third. When you water, water freely, until the water flows from the holes in the bottom of the pot. If that means less frequent waterings, so be it...

Can't rule out other causes here; has the tree ever had a dormant period? This is a Zone 5 hardy tree and would really like to be in cool to cold conditions for the winter; that's how they rest. Stay up for a few weeks straight to ses how trees feel about missing dormant periods for years on end...

If I'm still missing the mark let me know and we'll see if we can think of a new angle, but I'm betting on one (or all) of these to be the root cause..

Good luck,
Scott