Arlen,

The best size for a food plot depends on:

1. How many deer are consuming the forage.

2. How rapidly the forage is growing/recovering from being browsed.

3. The growing conditions.

4.  How many months you wish for the plot to attract/feed deer.

Obviously a plot would need to be much larger if 20 deer were feeding their daily compared to three deer.  Some crops like cover (if the growing conditions are good) can recover from being browsed faster than corn.  During severe droughts 20 acres many not produce as much forage as one acre during ideal growing conditions.  

I share this simply to say it may require some trial and error to determine the appropriate sized plot for your mission.  I suggest starting with an half acre or acre and see if there’s ample forage to attract deer throughout the season.  

I’d rather have a half acre plot that limed and fertilized appropriately than three acres of malnourished forage.  The better the quality of forage the more it will attract and benefit deer!

Enjoy creation,

grant