Tune up Planters to Improve Crop Yields, Quality, Ease of Harvest

Tune up Planters to Improve Crop Yields, Quality, Ease of Harvest

March 28, 2008 

Farmers who spend a little quality time with their planters before getting into the field this spring might be wearing bigger smiles after harvest this fall.

That's the advice from John Smith, machinery systems engineer at the UNL Panhandle Research and Extension Center in Scottsbluff.

Smith says tuning up planters has the potential to improve yields of most crops, particularly corn, and can improve the quality and ease of harvest for some crops, such as sugar beets. Smith is talking in particular about the planter's ability to provide a consistent spacing between seeds.

Modern planter designs are capable of very accurate seed spacing - as long as they are in good condition and operated properly. Seed spacing accuracy can be affected by many things; among them are field speed and shape of the seed furrow. Over the last four springs, Smith and his crew at the Panhandle Center have tested more than 300 planters, and almost 3,500 individual planter rows with the University's electronic planter test stand. Based on this experience, Smith says three primary planter problems lead to seed spacing inaccuracy:


  • planter seed tubes that show the differences between used tubes and new tubes
    These planter seed tubes (Deere, left two; Case-IH, right two) show the differences between used seed tubes (left) and new seed tubes (right ). The bottom inside surface of the new seed tubes are shiny and smooth while in the used seed tubes they're dull and slightly rough, like worn sandpaper. Smooth surfaces allow seeds to slide down without catching, resulting in uniform spacing in the field. The seed tube is a wear item and should be replaced as needed.
  • The seed metering mechanism. Fixing the seed metering mechanism is a matter of disassembling, inspecting and replacing worn or questionable parts. The mechanism should be tested on a good-quality planter test stand with the seed that will be planted.


  • The seed drop tube. The drop tube must be very smooth if the seed is to travel in a consistent manner from the metering mechanism to the seed furrow. Any roughness in the tube will provide an inconsistent time and path, resulting in inaccurate seed spacing. The tube can be checked by feeling the inside front surface of the bottom of the seed tube with the little finger. If it feels like worn-out sandpaper and is not as smooth as the outside surface of the seed tube, the planter cannot space seed accurately. The tube's smoothness can be tested on a planter stand, or with the finger test, and replaced if it is rough.


  • The planter drive mechanism's uniformity of rotation. To test the uniformity of the rotation of the planter drive, the planter should be raised on blocks or a secure stand. (To be safe, follow directions provided in the operators' manual.) Turn the drive wheel or put a wrench on the hex drive shaft. It must turn easily and without any jerkiness. Problems are commonly caused by bad chains, sprockets, bearings, and couplings between fold-up sections of wide planters. Irregular rotation also can be caused by insecticide and fertilizer applicator mechanisms.

Attending planter clinics is a good way for farmers to learn about planter settings and operation. The clinics bring together growers, implement dealers, seed dealers, agriculturalists, and university personnel. Together, they can provide a comprehensive approach to making sure that all the necessary elements are there for successful planting.

The University's role at these clinics is typically to test the planters after they have been inspected and if necessary repaired.

Even if they don't attend a planter clinic, farmers can turn to several other resources for help. Sugar beet agriculturalists have access to planter test stands. Operators' manuals provide information, and farm implement dealerships may have planter test stands.

David Ostdiek
Communications Specialist
Panhandle Research and Extension Center

Online Master of Science in Agronomy

With a focus on industry applications and research, the online program is designed with maximum flexibility for today's working professionals.

A field of corn.