Clipping is an important technique for tobacco farmers. It can improve the health and strength of a transplant, help keep all stem lengths and diameters alike, and be used to delay planting if field conditions are adverse. However, these benefits will only happen if you make sure to properly clip your transplants. Improper clipping can result in infection of collar rot, slower plant growth in the field and reduced stem length.
NCSU research has shown that maximum usability is obtained after just three to five clippings. Still, some growers clip 15 to 20 times. Typically, growers who clip too often have planted their seedlings too early. Extra time in the greenhouse at this critical stage exposes the transplants to disease while running up a grower’s power bill.
The NCSU guide recommends proper clipping should proceed at intervals of three to five days once the plant reaches a height of 2 to 2.5 inches above the tray. Set mower blades 1 to 1.5 inches above the bud. This method has proven to provide the ideal blend of uniformity, stem length and disease management. If you clip more severely, or closer to the bud, Virginia Tech researchers have shown these practices can have a negative impact on stem length and could result in slower-growing transplants in the field.
Also remember to thoroughly clean the mower and surrounding frame after each use by spraying a 10 percent bleach solution or commercial disinfectant on all surfaces. Additional research conducted by NCSU shows that the potential for collar rot infection increases when the clipping residue is left on the tobacco. Use high-suction rotary mowers or hand-collect residue after using reel mowers.