Preparing planter is essential with larger seeds.
Agronomy Bulletin 100 ─ Large Seed Soybeans
Soybean seed produced during summers with high heat and drought conditions can lead to increased seed size for the next growing season. These larger seed sizes, ranging from 2,000 to 2,750 seeds per pound, require more management to ensure accurate planting densities. Follow these steps to prepare equipment for planting.
Factors to Consider
- Planter settings
- Meter accuracy
- Air pressure
- Lubricant application
- Ground speed
- Examine seed size. Because seed sizes will vary, growers should visit their local dealer to get an idea of the range of seed sizes they will be working with at planting.
- Choose the correct seed disc or plate. In some cases, very large seed sizes will not adequately flow through metering devices, causing reduced plant densities or improper spacing. Planter manufacturers usually provide an alternative seed disc or plate with larger cells to accommodate seed size. Consult the planter manufacturer or owner’s manual for disc and plate recommendations. See Table 1 and Table 2 for examples.
- Check pressure settings. Larger seed requires more PSI to pull the seed through the unit. If using an air or vacuum planter, pressure settings may need adjustments.
- Apply lubricant. Always use adequate talc or graphite lubricant as specified by the manufacturer. When applying, incorporate the lubricant as the seed hoppers are filling versus placing all of the product on top of it. This will result in a more uniform application and better seed flow. Environmental conditions such as high humidity may necessitate additional lubricant to prevent bridging.
- Carefully monitor ground speed. At speeds of 5 miles per hour and slower, the seed disc cells populate more evenly and will result in fewer multiple seed events.
By understanding seed size and properly preparing the planter, growers will be prepared for seed size challenges well before planting begins. For more information, contact your local Mycogen Seeds commercial agronomist or trusted agronomic adviser.