Get abducted by space gnomes to tend their garden in this chill strategy sandbox

pcgamer.com:

Magically whisked across worlds by weird and slightly airheaded gnomes for your magical, inborn gardening ability, you must help them take a devastated wasteland and turn it into a lush garden. That's the plot for Horticular, a horticulture-based gardening game that wants to find interesting challenge with the puzzle of a healthy garden and beautiful layout.

To do that you'll need to find the right mix of plants and constructions to make the garden not just beautiful, but rich in diverse life. Different plants require different substrates—thick grasses, rich soils, dry savannah. Those plants are then combined in different quantities to improve the overall habitat, and when the right plants and terrain show up together you get… animals! 

Figuring out what goes where to attract new garden residents is how the game is played. The more happy plants and animals you have the more money you can make, and the more you can expand your garden to include new types of plants and helpful gnome residents.

Horticular has a demo on Steam, and playing that really crystalizes the main thrust of the game. There's a storyline to explore by fulfilling goals, and that involves keeping up the garden against accelerated forces of decay and agents of corruption. (Evil gnomes, naturally.) At the same time you're just doing some pretty chill gardenscaping, putting plants in nice places and attracting new animals to live there.

It's a game of creativity within constraints. You find magic plant nectar to get more decorations, then use those decorations to win the gardening competition. You enrich your garden with new residents to get more garden space—then figure out how to arrange that new space to get the most out of it and attract more new