flutter icon is not centered in container

I was trying to center the icon in a circular background but it failed even if I use a center widget as child unless increase container size.

    Container(
                  height: 22,
                  width: 22,
                  decoration: BoxDecoration(
                    shape: BoxShape.circle,
                    color: Color(0xffF7825C),
                  ),
                  child: Center(
                    child: Icon(
                      Icons.add,
                      color: Colors.white,
                    ),
                  ),
                ) 

Try this:

             Container(
              alignment: Alignment.center,
              height: 22,
              width: 22,
              decoration: BoxDecoration(
                shape: BoxShape.circle,
                color: Color(0xffF7825C),
              ),
              child: Icon(
                  Icons.add,
                  color: Colors.white,
                  size: 22 
                ),
            )