This looked absolutely wonderful when I saw it at Spiel '17, with all the cardboard trees covering the board. The idea is to plant your trees strategically, so that you can use the energy from the sun as it moves round the board. This lets you add seeds to the board, growing more of your species of tree.
Add in to this the tactical use of your trees as they grow to block the sun from your opponents. One more consideration: where you plant your trees influences your score as well.
There's plenty to think about, but the game plays quickly, providing an entertaining challenge.
For 2-4 players, aged 8+, playing time 15 minutes/player: £32.00 (£26.67 without tax outside the EU)
The photo (by Pevans) shows a game in play (green has almost half the board to themselves – don't let this happen!)