I have now cut cut this container in two, because at over 90cm in height it was taller than necessary. I will use the top part (with no base) as my cucumber container. I will fill it with home-made compost, giving the cucumbers about 50cm or so of rich growing medium, whilst at the same time providing full drainage. I think this container will be big enough for two cucumber plants. The lower bit I think will probably become a container for growing bush tomatoes, but I haven't quite decided yet.
This is where the cucumber container will go. In due course I will sink it into the soil by about 10cm to provide stability, but I'm not ready to do this just yet.
Across the top I will build a wooden frame for the plants to climb up, supported by the Callicarpa (at right) and the heavily-pruned remains of a Philadelphus shrub (at left). Hopefully the ferns you see in the picture will grow tall and hide most of the container, which though practical, will never be exactly beautiful. At least it's green!
Incidentally, the pile of unsightly "rubble" you see at the right of the photo above is my collection of stones and broken pieces of terracotta pot etc, which I use for creating a drainage layer when potting-up plants.
I need some ideas for what to do with the water-butt lid. It seems a shame to waste it...