How to get super mushroom

Answer from: Yosua
You need it? Okay, are you know, a table on near Inventory( Treasure Inventory)? Take 3 Lumber and press X when you holding lumber to that Table....... Like planting, just watering that lumber everyday, and than 7 days later, that lumber is growing mushroom. If that's your lucky day, you'll get that mushroom. But 90% I've play, that mushroom what I plant, is Supermushroom. You can't choose that mushroom. But I supposed, 90% is supermushroom. You'll not need that mushroom. What you need is Gold Mushroom! Same as supermushroom, plant with lumber. If you lucky, that's GOLD mushroom

Answer from: NOA
Just about you lucky or not. Put the lumber on the damp behind the store house. If you lucky, you get the super mushroom or gold mushroom. But both of it are quite rare