Now that you mention it, I've seen those plots from the windows of trains in Holland. Amsterdam is one of my favorite cities. The last time we were there, the Queen's birthday celebration was underway--an amazing experience.
And we spent a full day at the Keukenhof Gardens where some 7 million bulbs were blooming, most of them at once, or so it seemed.
I suppose everyone is on the honor system with respect to other people's plots?