How can I rid a country home of roaches?

My mother lives in the country in Louisiana. The roaches come in out the woods constantly. She has a muscolar disease similar to lupus and cannot tolerate the chemicals or the fumes. What safe product can i use for her home. We have used Borax, contacts every where, after awhile it is all ineffective. Help. Please. My email address is MariaChase9@aol.com