With all the frustration I have with plant location markers disappearing, I needed to come up with some way of keeping track of what is planted where. Most of my garden areas, like yours, are pretty large. It isn't enough to just indicate in my records that something is planted in the Lemon Garden because the Lemon Garden is at least 60 feet long. I know the genus of each plant by sight, but the tricky part is knowing the id of the specific cultivar. In most cases, I have many in each garden area.
I came up with the idea of driving tent stakes into the ground at 5 foot intervals. Now in my hand drawn map and in my database for the Lemon Garden I have twelve sections: 0-5 feet, 5-10 feet, 10-15 feet...
With my goal of getting rid of piles of hardcopy, I scan my hand drawn maps. I played with a rudimentary word document for the map concept too. I just insert a table with columns and rows and list the plants in each cell. The word document is much neater but doesn't have the personal flair of my hand drawn maps. Not sure which way I want to go with that.