Germinator closing wheels are designed to improve seed trench closure and create consistent contact between the seed and the surrounding soil. During planting, simply placing seed at the correct depth is not enough. The furrow also needs to close properly so the seed has access to the moisture and soil conditions required for germination. A key feature of Germinator closing wheels is the inner rim shoulder firmer. As the planter moves through the field, this design firms soil around the seed while closing the trench. According to ClosingWheels.com, the wheels are designed to reduce sidewall compaction, eliminate air pockets, maintain depth control, and completely close the seed trench.