Manganese deficiency may occur when the soil pH exceeds 6.2. If you suspect a manganese deficiency, collect soil and plant samples and have them analyzed. Boron can be applied as a preplant broadcast treatment along with other fertilizer applications, or with the preplant incorporated herbicide application. Cotton is very sensitive to soil acidity and has a high calcium requirement for quality lint production. Liming neutralizes soil acidity, supplies the calcium and magnesium required for plant growth and fiber production and promotes the efficient use of other plant nutrients.
Low nitrogen reduces yields.
Too much nitrogen causes excessive vegetative growth, makes pesticide coverage more difficult, delays fruiting and maturity, and reduces the effectiveness of defoliants. On deeper sandy soils where leaching is extensive, apply side-dressed nitrogen in split applications. Apply all nitrogen by mid-June. On heavy-textured soils where leaching is minimal, reduce total nitrogen rates by 15 to 20 percent. In most cases, apply all recommended P 2 O 5 and K 2 O at planting.