At its smallest size in the original Plants vs. Zombies, Sun-shroom produces 15 suns.
Sun-shroom is a nighttime mushroom that begins small and generates a small sun worth 15 sun units. After growing, it produces larger suns worth more, eventually becoming a stronger economy plant. Its staged growth is the key difference between Sun-shroom and Sunflower, whose output is consistent from the start.
The number is often confused with Sun-shroom’s planting cost, which is 25 sun in the original game. It is also easy to remember the later 25-sun output and mistakenly apply it to the smallest form. The first 15-sun drops are therefore both a defining mechanic and a reason Sun-shroom needs time to mature.
Sun-shroom appears in the game’s nighttime stages, where ordinary sky-generated sun is absent. Mushrooms help compensate for that shortage, but many begin weaker or require conditions before reaching full efficiency. Sun-shroom’s three growth stages reward players who protect it through the early part of a level, turning a modest initial investment into a more productive long-term source of sun.