|what is my soil lacking corn on cob only gets 3|
|Lots of things can cause smaller than normal ears (called 'nubbins'). Mosaic disease, high temperatures during pollination which causes sterility in the pollen, drought conditions, overcrowding, low soil fertility, silks damaged by insects, downy mildew (a diseases) or herbicide injury - 2,4-D applied during tasseling or pollen shed stage.
When you fertilize corn, use 2-3 pounds of fertilizer such as 10-10-10 for each 100 square feet of garden area. Spread the fertilizer evenly over the soil. Work it into the soil 3-4 inches deep. Rake the soil to smooth the surface.
Best wishes with your garden.