When I went out to check on my planter this morning, I noticed this weird granular substance and I have NO idea what it is. It wasn't there when I checked on it yesterday. This planter is only about two weeks old, give or take a few days. I used a brand new bag of soil recommended by the guys at the store. Could it have been somehow contaminated? If so, why'd it take so long to show up??
Looks like slime mold to me. At least this one was a sedate brown and not bubble gum pink or neon yellow. ...well so maybe NOT slime mold but some kind of fungus in any case.
It's a type of mushroom. Soon, you'll have the small granules growing into large mushrooms that can reach over 4 inches tall.
Since you have a lot of 'em, I'd recommend swapping the soil for some other type of soil. In my experience, these mushrooms like top soil as it is full of wood-like stuff.