Question About Rent Increase

[Justin Donohue]

I want to raise the rent on a tenant that I've had for two years. I'm increasing the rent $50 per month beginning January 1st. What is the best way to do this? My lease doesn't talk about rent increases at all. The tenant signed a one year lease that expired in January 2015 and they are currently month to month. I was planning on calling the tenant to let them know about the rent increase and then mailing them a letter just to give them something in writing. Should I be sending them something to sign, like an amendment to the lease? I'm in Baltimore County, Maryland if that makes a difference.