At first glance, you might think she's a pilgrim, judging by the way she's dressed.
But she's not really a pilgrim; she is a missionary for growing one's own food. We're talking tomatoes, string beans, beets, carrots.
It all began when Mavis totalled her grocery bill -- $800 a month.
"Last year in 2011, I was able to get down to $100 a month," she said.
That's $100 a month for mom, dad and a pair of teenagers.
Not everything she grows goes over well.
"I tried making a swiss chard smoothie," she said. "They weren't so excited about that."
So swiss chard was a bad idea. And swiss chard smoothie a really bad idea.
Her kids' reaction: "They think I'm on crack," she said. "My son would like to have a cupboard full of Doritos and Wonder Bread."
I got a feeling Black Fatty isn't all that keen on Mavis eating homegrown stuff. Don't play chicken, chicken; Mavis will only eat your eggs.
She hopes to grow a ton of food.
"I bet I'm going to get 25 hubbard squash, and I'm very excited about that," she said.
She's also going to get 500 pounds of tomato and the dreaded swiss chard.
And the truth is Mavis really doesn't like swiss chard. So what does Mavis do with swiss chard? She'll trade everything she doesn't need for meat, and perhaps for her son -- Doritos.
This garden has an upside even for kids.
"Actually my daughter and I just got back from a trip to Europe paid for by not shopping a the grocery store," she said.
Mavis says her neighbors love fresh produce. In one recent trade, she got American cheese, sausage, granola, organic peanut butter and a can of Coke.