I wouldn't hang a gate from this post. Either swing the gate from the other side, or use a different (i.e. stronger ) material for the post. If you use wood, do not put the post in contact with the ground, just attach to the house (preferably with flashing between it and the house ). Since you're hanging a gate off of it, 3/8" lag bolts would be better.

Another option would be to use the standard vinyl post, set in the ground just to the side of the foundation, then install a short section of fence to close the gap between the post and the house.