In recent years, there has been renewed interest in applying a small amount of fertilizer in the seed furrow when planting corn (i.e., pop-up fertilizer). Standard starter fertilizer use has involved placing fertilizer (at a much greater rate than pop-up) about two inches to the side and two inches below the seed when planting (i.e., 2x2 placement). The interest in pop-up fertilizer compared to 2x2 placement has occurred because using less fertilizer means less material to haul, the application equipment is easier to maintain, and because of claims of obtaining a faster crop response because the fertilizer is right next to the developing corn roots. This project compared the response of corn to pop-up fertilizer and a standard 2x2 placement. Our results suggest that pop-up fertilizer does not result in a faster early-growth response than standard 2x2 placement. If early-growth responses do occur, pop-up placement is usually similar to 2x2 placement in rate of early growth. We also found that normal fertilizers used in corn production (i.e., 10-34-0 or 30-0-0) will provide similar crop responses when compared to the more expensive pre-made pop-up fertilizer packages. Finally, our results suggest that caution should be used when using pop-up fertilizers because significant corn grain yield reductions were observed in a few environments.