How to keep Rats out of my house/Garden?

Question:How can we get rid of rats in our garden traps dont work
i am frightened they will come into the house i have french doors which i would like to keep open any one have any idear's on how to repel them from coming into the house/ garden without keeeping the door shut, i have those plug in to repel but am worried they might not work.

Answers:
there are two species of snake that make excellent deturents. The King snake and the chicken snake. Both are non poisonous and very docile. find one and let him roam free in the yard. All varmints and poisonous snakes will be effectively terminated