Small-seeded crops like small grains and canola are usually seeded with box drills or air seeders. The issue with most box drills or air seeders is that they offer poor seed singulation and uneven depth control, which can lead to uneven seed distribution and uneven seedling emergence. This can be especially problematic in no-till/high residue scenarios. Recently, row crop planters have been adapted or custom-built to accommodate smaller seeded crops, to address issues of poor distribution and uneven seed planting depth. Depending on the configuration of the planter, row spacing can easily be switched between narrower row spacing and wider row spacing to accommodate row crops like corn or sunflowers.
The major disadvantage of using a row crop planter for small-seeded crops is that no large manufacturers offers off-the-shelf solutions. This leaves end users customizing stock units with aftermarket parts or building custom units. This can result in high up-front costs. At the same time, some air seeder manufacturers are beginning to offer seed metering solutions that use seed plates for seed singulation and automatic depth control for each row unit, using mechanisms similar to row crop planters.