Plant Path Strategy: Solving Without Guessing
Every Plant Path board has exactly one solution. That is not a promise about difficulty; it is a promise that deduction always works. Here is how experienced players read a board before they draw a line.
Corners first
A corner cell touches only two others, so the line has to enter it through one of those neighbours and leave through the other. That fixes two segments of the path before you have touched the board. The one exception is a corner that holds circle 1 or the last circle, where the line only enters or only leaves. Either way, a corner is the most constrained cell on the board, and the constrained cells are where a solution is found.
Edge cells touch three others, so they are the next place to look. Once one of an edge cell's neighbours is ruled out, the other two are forced.
Never seal off a region
The line must fill every cell, so any move that cuts a pocket of empty cells away from the rest of the board is wrong, even if it looks harmless in the moment. Before you commit to a turn, glance at what it closes off. If a group of empty cells would have no way in and out afterwards, the turn is wrong, and the correct one is usually the other option you were weighing.
The same logic works in reverse: a pocket that can only be entered from one cell is a dead end, so the path must finish there, which means the last circle is inside it. If it isn't, the pocket has to be opened up by a different route.
Count the cells between circles
The path from circle 3 to circle 4 has to use a certain number of cells, and that number is set by which cells the rest of the path cannot reach. If a cluster of empty cells lies between 3 and 4 and nothing else can get to it, the 3–4 segment has to sweep the whole cluster on its way. Thinking in segments, one circle to the next, turns a 7×7 board into a handful of short problems.
A lightweight checkerboard trick helps too. Colour the cells in your head like a chessboard. The line alternates colours with every step, so on a board with an even number of cells the first and last circles sit on different colours, and on an odd board they sit on the same one. When a segment looks possible but the colours don't add up, it isn't.
Rocks are corners in disguise
A rock takes a neighbour away from every cell around it. A cell wedged between a rock and the edge of the board is a corridor with only two ways through, and a cell tucked between two rocks may have only one, which makes it the end of the path. Treat each rock as a new set of corners and read them first, before the open middle of the board.
Walls do the same job
A wall closes one edge of a cell, so a cell with a wall behaves like an edge cell and an edge cell with a wall behaves like a corner. Walls arrive on the high ladder, past level 40, and the boards there carry fewer numbers than the learning levels precisely because the walls do the constraining instead. Find the walls, work out which cells they have turned into corners, and the board opens up.
Work from both ends
Circle 1 is the obvious place to begin, but the last circle is just as informative: exactly one line arrives there and none leaves. If the last circle sits in a corner or a corridor, the final segment is fixed and you can plan backwards from it while drawing forwards from 1.
When you are stuck
- Slide the line back to the last cell you were certain of. Tapping a cell the line has passed through trims it back to there.
- Look for the smallest region of empty cells left and ask how the line gets in and out of it.
- Take a hint. It lights the next stretch of the correct path from the end of your line, and you carry on yourself.
- Slow down. The levels have no clock. The daily puzzle records your time, but only against a par, and the board is the same whether you take two minutes or twenty.