Soil and Nutritional Summary

Liming will increase pH, neutralize exchangeable aluminum and increase base saturation. Cotton will also benefit from increases in cation exchange capacity (CEC) and the availability of N, S, P, B and Mo. Liming can promote improved root growth, allowing better nutrient use efficiency. Liming should be performed at least two months prior to planting with subsequent incorporation where possible.

In order to assess the nutrient requirements of the cotton crop, soil and leaf analysis are important tools and must be used. Of the specific nutrients, particular attention should be paid to potassium and calcium as both are key to improve yield and quality.

Nitrogen prolongs growth and increases the number of main stem nodes and fruiting positions on lateral branches. It also aides in boll formation. 

Potassium is integrally involved in metabolism and regulating water in the plant. It is an enzymatic activator and is essential to photosynthesis. Apart from its enzymatic functions, potassium plays a particularly important role in fiber development in cotton. A shortage will result in poorer fiber quality and lowered yields. K also reduces the incidence and severity of leaf spot diseases. 

Calcium improves cell wall strenght and integrity and is crucial for overall new cell development. In cotton, the fruiting activity is influenced by the level of available calcium in the soil. Calcium also serves to increase salt tolerance. In experiments where cotton was grown under varying levels of calcium, the fruiting index increased with each increment of added calcium. 

Cotton is especially vulnerable to boron deficiency. Boron is an essential element that cotton needs during all stages of growth and fruiting. Supplying adequate boron will help cotton: 

• Develop and retain more squares
• Increase pollination and boll set
• Move nutrients and sugars from leaves to the fruit
• Produce strong, well developed fibers
• Speed maturity

Guidelines for Nutrition Management in Cotton