I am an organ, but I am also a verb. Digital me sometimes cost money, but sometimes is free. I come in many colors, but I need to watch out for the sun.

Three is common, four is rare, more is an anomaly. Pluck me gently if you wish, for I may bestow you luck, but only if you look below.

Golden crescent fruit, Doth slip from its yellow skin, Sweet within, dost hide.

I dwell where roots begin to grow, And mark where tales no longer flow. First in the forest, last on the page; What am I, in nature and in sage?

I'm still in my early stages. Fully grown? I am not. Take away my center, and I become molten hot.