1- Watering - under or over.
2- Doing many things at the same time. Like reppoting, hard pruning, barerooting, wiring and fertilizing.
3- Doing things at the wrong time, specially with pines.

Hi Clicio,
I currently have 11 little trees which I'm training … some are closer to being pre-bonsais, some need more years and work… I have killed 3 in the last couple of years, and the root cause has mostly been watering… in particular during summer 2017, so hot here in Milano.
Definitely, it took me about 3 years to learn to water properly...

Clicio wrote: 1- Watering - under or over.
2- Doing many things at the same time. Like reppoting, hard pruning, barerooting, wiring and fertilizing.
3- Doing things at the wrong time, specially with pines.

4. wrong location

And in general: not understanding that it concern trees and treat them like puppies that must not get cold outside, need to be kept warm and need to be fed (and giving them horrible puppy-names. OK, that won't hurt the tree).

Auk wrote: ...and giving them horrible puppy-names. OK, that won't hurt the tree.

Yes, but it hurts my ears...
"Matilda" for a pine, or "Alfred" for an Acer is really humiliating the trees.

Clicio wrote:

Auk wrote: ...and giving them horrible puppy-names. OK, that won't hurt the tree.

Yes, but it hurts my ears...
"Matilda" for a pine, or "Alfred" for an Acer is really humiliating the trees.

Or Bonnie (see what I did there? Hilarious isn't it?)

Go-shin though is a great name for a great piece of art.
en.wikipedia.org/wiki/Goshin

Yes, location.
Almost all trees need full sun, breeze, dew, rain.
Which means being outdoors.

Naaaah .... they ´re simply being killed by ....

find out here

Mimo, thank you, I needed THAT!

You´re welcome Glad to be of service