Here in the Midwest it's, "Knee high by the fourth of July" for a good crop.Do people your way say, "As high as your eye on the 4th of July"?
Response to below (to save lines): Same here.
The expression is wrong! The stalks are nowhere near your eye's height in early July.
This year some fields were already beginning to top (tassel) out by then. Early planting, decent weather and lots of rain all contributed.