The neighbouring boxes stand beyond the edges of the screen and come out only when the map is dragged. Their plants are already in place: there is no loading to wait for.
On the box at the end of the bar the gesture leads nowhere - the map springs back.
While you are flipping through, the box bar does not reorder itself: a swipe there and back returns you exactly where you started. A moment after you stop, the bar sorts itself by recency - the box you stopped on becomes the first.
The gesture does not interfere with the usual work: scrolling the page up and down, moving a plant with a long press and selecting a group of cells work as before. While a move or a selection is going on, flipping is switched off.
The gesture is a helper path. All the same is available by pressing the box button in the bar.