When we arrived back home this summer, we found this mystery plant growing where we had just put in the
stepping stones in the garden the city dug up for the water main/sewer repair.

It is huge. It is about 3 ft now, and that is fast for 2 months of growing!! Has small light orange flowers (that resemble squash flowers)...but they fade very quickly and form the seed pods I tried to get a picture of.

My wildflower book does not have this in it.
I think it came from the sacks of top soil we put down, along with sand for the stepping stones.

The plant is not attractive but the seed pods look very familiar to me. The leaves are huge and resemble Chinese Lanterns. Only they are much larger and lighter green.

I am saving the seed pods for across the street, for my wildflower area. But the plant I will cut down (not pull up) to see if it returns next season.

Anyone know what this is? I appreciate all responses!