Adding a touch of orange seems to really light up a room. Seeing these photo comments is making me want to add more orange to my house! :)

The box is locked with a mortice key (5 lever) and a lock that is welded into place. Not sure you can see the key hole on this image - but it is there. It’s also welded to the ground and is made of structural steel - using intimidation tactics to dissuade the opportunist. The added security is that it’s actually disguised as a planter and so most people are surprised to find it provides nearly 4sqm of extra storage. If you are in London, come for a tour!

I thought this was quite good value from Homebase as it’s quite big but maybe too plain? Matalan also have some nice gold metal ones but the holders are quite shallow for normal plant pots

Me again:) I’m no expert but have a few ideas. Unsure what aspect your planter is facing, wether it’s in sun or shade. Bamboo would work well just be sure to research the variety. Any of the Sasa (broad leaved bamboo) will grow tall, but be aware that these spread like mad via underground roots so I’d add a weed proof membrane to the base of planter and after a few years they might not look so great in a container. Chimonobambusa Marmorea (marbled bamboo would be a good choice if it’s in shade. Besides bamboo there are a few shrubs and that can do well in containers, Camelias can do well if in shade, Daphne would be lovely if it gets some sun and smells divine. Laurel will pretty much thrive anywhere and you can prune it to whatever shape you like. Trees I’m unsure on but I think so long as they’re grown on dwarf rootstock they might be ok but I’d rather see a larger container. Thuja Occidentalis will do well if you want a wall of green as would yew but it’s slow growing. Ferns can look great if in shade, Polystichum Setiferum (soft shield fern) or Mattecuia (ostrich/shuttlecock fern) can grow fairly tall. Can’t think of any more atm but I’m sure there are many more. What I would do however is treat the planter to some wood preservative or other chosen treatment and line the inside with plastic (remember to put drainage holes in), this will help stop the wood from rotting.