Although the operator may have correctly set the depth adjustment, depth wheels may not be firmly in contact with the soil and the planter unit may be riding up on the seed opener. Additional down-pressure or weight is necessary for the seed opener to penetrate to planting depth. Many planters have an adjustable down-pressure spring to vary the amount of surface pressure and coverage for supplying adequate soil contact. Spring pressure may need to be increased in drier surface soil for adequate soil contact and to help bring moisture to the seed. Pressure may be decreased after surface soil moisture has been recharged by rainfall to avoid overcompacting soil around the seed.
Adequate water is especially important at planting time.
Without sufficient topsoil moisture, seed germination could be impaired, resulting in low plant populations and low yield. This information subject to a usage policy .