Sprout Planet

Sprout Planet is a free idle game you can play in your browser with no download. A small gray planet turns in the night sky, dead from pole to pole, and your job is to make every tile of it green again. One tile glows when you start. Tap it and a seed pops in, a sprout pushes up, and the grass begins to creep to the tiles around it on its own. The bar at the top counts down how many gray tiles are left, and when it reaches zero the planet is done and you fly on to the next one.

Every green tile earns seeds, a few each second, and seeds are what you spend. A new seed planted far from the grass you already have opens a second front, and two fronts spread much faster than one, so where you plant matters more than how often. Rocks block the grass until you tap them apart, three taps for a big one. Drag the planet, or use the arrow keys, to turn it and find the gray corners on the far side.

After a while you can build greenhouses. A greenhouse is a glass dome on its own tile, and the little gardeners who live in it walk out with seed sacks and plant every gray tile within three steps of their home. Put one on a far corner the grass will take ages to reach and that corner fills itself in. Upgrades make the whole planet faster: seed yield makes every green tile pay more, gardeners adds more of them to each greenhouse, rain sends extra clouds across the sky, and bees turn grass into flowers that pay four times as much and sometimes burst-plant every tile around them.

There are seven planets, and each one adds a new problem. Meadow is the gentle first garden. Tide is mostly ocean, and grass never crosses water, so every island needs its own seed or its own greenhouse. Dune is dry sand that only takes a seed while a rain cloud is passing over it and keeping it wet. Rime is capped with ice that melts only where green tiles surround it. Ember has volcanoes that rain ash back onto your grass until you ring each one in green and put it out. Gale has a steady wind, and white streaks show which way it blows: grass races downwind and barely creeps against it, so the seeds go on the upwind side of the gray. Dusk turns slowly through day and night, and grass only grows on the sunlit side, unless a greenhouse lamp lights its corner through the dark. From Tide on there is weather too: a high tide, a sandstorm, a cold snap or a gust is announced eight seconds before it arrives, a dark cloud and flashing tiles mark where, and it turns a few tiles of grass back. Grass within three steps of a greenhouse is sheltered, so where you build decides what a storm can take.

Finishing a planet gives you golden seeds, which make everything grow faster for good, on every planet after it. Each planet also earns one to three stars for how quickly you turned it green, and a little clock under the bar shows which stars are still in reach. Tap the planet name to open the galaxy map: any planet you have greened can be replayed for more stars, your planet in progress waits for you, and the first three-star finish on a planet pays one more golden seed. When all seven are green, a new galaxy of seven planets starts with your golden seeds still in your pocket. While the game is closed your planet waits exactly as you left it; only your grass earns a few seeds, for a few minutes at most, and a short video can double them. A Grow ×2 button speeds everything up for a couple of minutes if you want it, and a daily reward adds seeds when you come back. Your planet, seeds, greenhouses and upgrades are saved in your browser.