Best place in Tokyo to buy outdoor (balcony) decorations?

I have a big balcony that I want to use more. I already bought small garden furniture from IKEA, but I would like to make it more "garden-like". I have a lot of hooks on the inside of the balcony which are supposed to be used for hanging clothes, but I never dry things on the balcony, so I was thinking of getting some fake leaf garlands and hang up. I also bought a wooden screen that hides the aircon unit, and it also has small holes that I could potentially decorate. Would also love to hang up some life plants that can handle both winter and summer (of course on the inside of the balcony).

Does anyone know a good place in Tokyo where you can get these kind of things? Nitori and IKEA are both close to me but a bit limited in terms of outdoor stuff.