Growing Cotton – Crop Nutrition 101

What you need to know about cotton fertilization, best practices, and more

Crop Nutrition Information for Growing Cotton (Gossypium hirsutum L.):

  • Cotton peforms best in soil pH between 5.8 and 6.5

  • Fertilizers are most efficient when soil pH is between 6-7

  • Liming is recommender for fields with soil pH less than 6.0

  • Cotton emerges quickest from warm, most soil

  • Germination can be hindered by temperatures below 60F or less than adequate soil moisture

  • Cotton is a DD60 crop which means it grows more slowly on days below 60F

  • Cotton plant development, including vegetative and reproductive stages, is predictably regulated by environmental factors, heat accumulation dictates development as much as time

Key Nutrients: 

  • Nitrogen is integral for healthy cotton production 
  • The recommender best practice is to  side dress N just before early square, which is closer to the period of substantial nutrient demand by the cotton plant 
  • In addition to N, Phosphorus (P), Potassium (K), Sulfur (S) and Boron (B) are nutrients of importance in cotton that must be managed properly for optimum fiber quality and lint yield. 

Nutrient Removal by Cotton 

Nutrient balance is key to quality yields.  

2 bales/A (cotton lint & seed lb/A) – (Alabama Extension: ANR-0449) 


N – 63  

P2O5- 25  


Ca -4  


S -5 

Role of Nutrients:  

Key quality and yield parameters can be affected by different nutrients. See how they can influence your harvest. 

+ = improving 

– = decreasing 

+/- = different results, depending on the rate of nutrient applied 


Yield: N++, P+, K++, Mg+, Ca+, S+ Quality: N+/-, P+, K++, Mg++, Ca++, S+ 

Cotton Field
Cotton Harvest


  •  Total N rates for cotton should be based on soil type, previous crop, field history and yield potential.  

  • The best strategy is to apply the recommended K fertilizer at planting based on soil test results follow by a foliar feeding of K during peak bloom.

  • The best strategy is to apply the recommended P fertilizer at planting based on soil test results. 

  • Polysulphate is a neutral fertilizer that supply base cations such as Ca, Mg, and K, so while it may not increase the soil pH it won’t lower the pH either. Yearly application of Polysulphate can be used to supply Ca, Mg, & K to maintain soil pH levels reducing the frequent need for lime application. 

  • It should be based on the soil type and conditions. Soil with high affinity for P fixation and planting in cooler soils could benefit from a starter fertilizer such as ICL Agrolution PH low 11-45-11 with 2% Zn. 

  • Polysulphate not only supplies S (which is critical for maximizing yields), but it also supplies three mineral nutrients (Ca, Mg, & K). Mineral nutrient deficiencies can limit the growth and yield of cotton, particularly when they occur during the reproductive phase. Producers should aim to eliminate the chance of mineral nutrients becoming limiting during the flowering and fruiting stage by applying 100- 200 lb/A of Polysulphate at planting.  

  • During the growth of the crop, leaf tissue analysis are the best available tools to determine e whether the crop is taking up sufficient nutrients to be corrected by side dressing or foliar application if necessary. 


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