The tank includes an overflow pipe, out of which small amounts of water sometimes drop.
Because it’s only a small amount of water, I made no special arrangements for it. It drops straight onto part of the side footpath and (theoretically at least) drains away.
After a little while, I noticed some moss had started to grow on that section of footpath.
Fast-forward to 2015, and the moss has grown and been joined by who knows what from who knows where… it’s now a proper little garden — probably of horrible weeds, but still.
I could cut it all back, but I’m intrigued to see how much it grows from here.
If my blog goes silent, you’ll know it really was a triffid.