Renting a rural house. Hasn't been used in a year. It's clog 3 weeks ago was caused by too much toilet paper. I used charmin and Kirkland paper. Was fine until today. Water drains and goes back to normal but today my washer backed up into my shower and toilet. Landlord accuses me of flushing paper towel and stuff. I know better. Plumber coming tomorrow. She told him to check if the septic tank needs emptying. There is a bit of a smell in the yard. Guesses on what's wrong?

Guessing septic needs pumped out.
But you could be clogging drains as well. I'm sure you know that when on septic, never put anything down a drain other than toilet paper (and human waste). Not even a tissue from blowing your nose, nor a tampon or mini pad. Not a single bit of food. Go easy on bleach and cleaners. Put a drain sock on your washer and clean it often (washers drain very fast, so are prone to backing up into nearby places).
Some say a rule of thumb for cleaning out septic is every 8 years of continuous use, but how many people? There's no way to know with a rental.

With septic tank, you have to be very careful what you put down the toilet. As mentioned in above post, no Kleenex, paper towels, feminine products, etc. As far as back ups go - I think the problem is not septic, but drain that connects house and septic. Since the house was not used for a year, you should snake the main line.

Hope that helps

Milo