Bob Ross would be so proud of this game.
Photosynthesis is a, uh... mm... it's not worker placement... 'strategy', I mean, everything is a strategy game... it's a game about growing trees, really. That's what you do. You plant trees and watch them grow, as long as they're getting sufficient sunlight.
That's it! It's a sunlight absorption game!
Here's how it works. You start the game with a small collection of trees and seeds to plant in the forest. As you plant more trees and the sun revolves around the forest (I know, I know, just go with it), your trees gather light, which gives you points to spend on more trees and seeds. Seeds lead to small trees, and trees can grow from small to medium to large; the bigger the tree, the more light points you get when the sun hits them. However, they need to be positioned to catch the sun, which means being either taller than the trees in front or beyond the reach of their shadows.
Once large trees are on the board, the owners of those large trees can spend light points to remove them for a scoring token. The closer you are to the middle of the forest, the better the soil, and thus the more points you get for scoring a tree there. Trees in the middle often have a harder time gathering light when they're smaller, but that's ok; all of your light points go into one pool, so the trees routinely gathering light on the outside can fund the growth of trees on the inside. It's like a hippie commune that met its final destiny and actually became the trees they love so much.
The game has a very interesting way of balancing itself out. There are no catch-up mechanics per se, and a player who pulls in a bunch more light points than their opponents can look like they'll snowball out of control with the number of trees they can grow or embiggen (it's a word). And, if completely allowed to do so, they will. But the sun goes through three rotations, sitting on six different positions on each one, and it's almost impossible to not be in a favorable position with regards to blocking your opponents and getting more light at least some of the time unless you're completely botching the game.
It could happen if a particularly experienced player and someone who doesn't know the game but tries to be too clever match up, but most likely a snowball occurs when two players target each other and a third grows, mostly unmolested. There are enough turns in the game, though, that the third player can then be targeted for getting too far out front. So there are no self-correcting functions for a game that might get out of hand, but there are ample opportunities for players to deal with the problem.
The art is lovely, and having bundles of actual tree figures to put together and place on the board feels fantastic. Lay a seed, pop a tree down, replace a tree with a bigger one, chop down the giants... it's all viscerally solid. It's one of a number of recent releases that is simply beautiful to look at, the sign of a designer trying to take one of the things unique to board games—actual physical pieces to play with—and turn them into a major plus.
As with many games which have that lovely aesthetic, however, there's a sense that the art is top-quality to make up for the gameplay. The first time you play it, it's like you've been handed a familiar but still noticeably different type of puzzle to solve. The second time, with experience in hand, you build a strategy around how to get your big trees out and score some points, because in most games players won't be able to do that too many times. The third time, all the ways your opponents messed with you in the first two games come to mind and filter more fully into your strategy. Those games are fun.
The ones after it...
There are going to be people who could play this game again and again and again and adore the hell out of it. Some of them will be relatively casual gamers who particularly enjoy the theme and art, and to be fair, that's probably the main audience for this game. I think that a lot of what will drive people through multiple playthroughs, however, is having the right opponent or opponents to turn the game into a proxy for trying to soul-read each other's strategies, which is not the same as the game itself offering tremendous replayability.
A strong and important market exists for games that are better designed than the buy-at-Target classics, yet appeal to casual gamers and would go well on their shelves or the shelves of those who often find themselves introducing casual gamers to the hobby. It's for people who don't play many games but are very curious and ready to throw themselves into the medium depth of the pool, or those who have played the real entry-level stuff like Catan and want something that doesn't rely on any luck whatsoever. Photosynthesis fits that niche. Consider this a strong recommendation if that's the type of game you're looking for, and a 'play someone else's copy' recommendation if it's not.
Score: Eight happy little trees out of the eleven we have enough paint for on the palette.