Across the U.S. Cotton Belt, potassium (K) deficiency symptoms in cotton (Gossypium hirsutum L.) have become more common over the past decade. In 2015–2017, an experiment was conducted in Alabama, Arkansas, Louisiana, Mississippi, North Carolina, Oklahoma, South Carolina, two regions in Texas, and Virginia for a total of 23 site‐years. The objectives were (a) to quantify soil K levels at‐depth in representative soils where cotton is commonly grown in major cotton production regions with observed K deficiencies; and (b) to evaluate the effects of application method and K rates on cotton lint yield, loan value, and return on fertilizer investment. Granular and liquid potassium chloride were broadcast or injected, respectively, 2–4 wk prior to planting at 0, 45, 90, 135, and 180 kg K₂O ha⁻¹. Locations other than Texas and Oklahoma generally had soil K levels <less than 150 mg kg⁻¹, the Mehlich III critical K level, and thus, a yield response to applied K fertilizer was expected. However, among the 23 site‐years, a treatment effect was determined at 5 site‐years. Two of those, Williamson County, Texas, and Virginia endured severe moisture stress and resulted in low yields (1,653 kg lint ha⁻¹). Inconsistent yield responses among locations indicate that K dynamics in the soil–cotton plant system are not well understood and deserve continued investigation.

By improving soil properties, cover crops can reduce wind erosion and sand damage to emerging cotton (Gossypium hirsutum L.) plants. However, on the Texas High Plains, questions regarding cover crop water use and management factors that affect cotton lint yield are common and limit conservation adoption by regional producers. Studies were conducted near Lamesa, TX, USA, in 2017–2020 to evaluate cover crop species selection, seeding rate, and termination timing on cover crop biomass production and cotton yield in conventional and no-tillage systems. The no-till systems included two cover crop species, rye (Secale cereale L.) and wheat (Triticum aestivum L.) and were compared to a conventional tillage system. The cover crops were planted at two seeding rates, 34 and 68 kg ha⁻¹, and each plot was split into two termination timings: optimum, six to eight weeks prior to the planting of cotton, and late, which was two weeks after the optimum termination. Herbage mass was greater in the rye than the wheat cover crop in three of the four years tested, while the 68 kg ha⁻¹ seeding rate was greater than the low seeding rate in only one of four years for both rye and wheat. The later termination timing produced more herbage mass than the optimum in all four years. Treatments did not affect cotton plant populations and had a variable effect on yield. In general, cover crop biomass production did not reduce lint production compared to the conventional system.