Hi Janice,

I belive that all the plants listed would fair quite well in troughs. They are all quite popular plants for bonsai, so well suited for container culture. After a while, if they start to lose their vigor it may be necessary to lift them and trim the roots (check some bonsai books to see how to do this properly), or move them to larger containers, especially with the cotoneaster and elm. The Pine and Spruce are slower growers and should be OK in a container for quite some time.

Good Luck,

-Cody