What tall plants to plant in tall troughs

[gardenhelppls]

I have treated myself to some rather nice white terrazzo troughs to create a wall barrier between patio and garden and I want to make them have maximum impact. What can I plant in them which will look wow. I think tall flowers and maybe some smaller vivid purple campanula

Any recommendations? thanks!

[sackrifice]

How big? Can you get some fruit trees in them?

When planting containers you need a selection of plants not just one, so that one is coming into life when the others are starting to fade.

I like to put tall things, medium things, ground cover and then some trailing plants in. i usually go to the local nursery and see what they have that I like and get that.

[gardenhelppls]

They are 35 x 75

[florentina1]

Actaea are stunning. Black leaves with white flowers and then amazing seed heads through winter. Also Black Sambuca and Cornus Midwinter fire will give you year round drama.

[Beebumble2]

Tall ornamental grasses and tailing plants such as Bicopa.

[yamadori]

How about some canna lilies?