First off let me tell you this wasn't my idea. I gathered it from this blog Another Year Without Groceries- they went a whole year with out groceries. Granted they live in southern California and can grow near anything year round.
Anyway, the idea is an appealing one when you live four miles from a very small town grocery store and an hour and half drive to the nearest big grocery and retail stores. We did do some pre-purchasing in December to prepare for our month (January) without grocery shopping. Mostly we stocked up on dry goods - flour, sugar, cereal, cliff bars, paper products, frozen vegetables, and a little meat for the freezer. Then we thought of any exceptions that we wouldn't be able to stock up on or provide from the farm example we have chickens so we don't have to buy eggs. We came up with two grocery store exceptions: Milk and drinking water. Our well water isn't safe to drink as were the results 13 years ago - the water needs to be retested (on the 'to do list'). We also didn't restrict our eating at restaurants mostly because we rarely do and it is always a treat. I think we ate out twice in January and filled our ice cream craving at Cold Stone once.
It was a good month, it wasn't that hard not to buy groceries. We don't have TV programming (aka cable/dish) and don't get a newspaper so there wasn't much in advertisement 'here buy this' to deal with. The local grocery store does mail out a flyer but I quickly learned to just throw it away with out looking.
I did have trouble once while at Walmart - I had to have tortilla chips, I was given homemade salsa and needed chips. Yes I could have made chips and I have found a recipe but I'm not too hard on myself. Oh and on the 31st of January hamburger was really on sale at the local in town grocery store so we bought some having been out of meat for the last week. All in all those were the only two breaks in our 'no groceries'.
Richard and I hope to continue this trend by purchasing less and less at the grocery store. Our plans include a large produce garden, getting a milking animal (cow or goat), more meat animals, and lots of canning and preserving.