Looking for Maria Hesse and Georg Lortz Ontario Canada

I am looking for information of my great grandparents Maria Hesse born 31 May 1836 in Hessen Darmstadt Germany and Georg Lortz born 27 July 1833 also Hessen Darmstadt Germany. They came to Canada, settled in the Kitchener area, lived in Listowel and raised 5 daughters - Augusta born in 1881 was my great grandmother (she married Arthur Parlane). Any information is welcomed. Also I am not sure how to go about researching in Germany. Maria was apparently from The Royal House of Hesse, but married a commoner, Georg Lortz. Linda Veronese