A photo would be best... otherwise, maybe it actually is Arum maculatum or italicum - they pop up on their own like a weed.

Arum maculatum is commonly known in Sussex as Lords and Ladies or Red Hot Poker.

I agree with out a photo difficult to say. Arum maculatum our native arum can be a weed if it is not what or where you want it. it has many common names 'lords and ladies' and 'jack in the pulpit' are the 2 local to me.

Oh yes! Jack in the pulpit! I'd forgotten that one. Saw some lovely examples on a country walk yesterday, in the right place, along the edge of woodland!