5 MIN READ
Cotton Planting and Stand Establishment
May 26, 2022
Cotton Product Selection
Cotton growers should choose cotton seed products that demonstrate consistently high yield potential over at least a 3-year period and in multiple locations. It is not advised to select the top yielder at any single testing location or year. In addition, seed products should contain suitable trait packages for management efficiency (such as growth habit and response to plant growth regulators) and pest/disease resistance. Growers should plant several different products with differing maturities and/or spread out planting dates to increase harvest efficiency and reduce risk of yield loss associated with adverse weather or environmental conditions. When testing a new variety, planting on no more than 10 percent of your fields in the first year is advised. If successful, increase the acreage slowly, until several years of yield data are obtained and there is confidence in the stability of the product.
Seed treatments are important to consider when selecting cotton products to help protect seedlings from certain common early-season diseases and insects, and to improve early-season vigor. For more information on cotton seed treatments, visit Acceleron® Seed Applied Solutions at: www.cropscience.bayer.us/seedgrowth/acceleron.
Seed Quality
When choosing cotton seed, check for seed viability information from standard germination testing on the seed bag. This test is used to estimate the percentage of seeds likely to emerge under ideal, warm growing conditions. The percentage of seeds that germinate should be at least 80% of total seed tested. A cool germination test simulates less-than-ideal conditions (soil temperature of 64.5 °F) to estimate seedling vigor. Results should have a minimum germination of 60%. Contact your seed dealer or the seed company to obtain cool germination data. Growers may also see results reported as the seed vigor index, which is cool and warm germination numbers added together. High-quality seed will have a vigor index of 160 or greater (e.g., a warm germination value of 90 + a cool germination value of 70 = 160).
Seed size may also impact seedling vigor. Under ideal planting conditions, seed size may not matter, but under suboptimal conditions, such as cool temperatures or soil crusting, smaller seed may have lower vigor than larger seed with more nutrient reserves. Therefore, be especially careful when planting small-sized seed and seed with low cool germination test ratings. This seed should be planted in conditions as ideal as possible.
Cotton seed should be handled carefully and stored in a cool, dry environment. Storing in a warm, humid environment can decrease germination.
Soil Conditions and Weather
Plant cotton according to soil temperature as opposed to calendar date. Soil temperature should be a minimum of 65 °F within the germination zone, preferably closer to 85 °F, and soils should be moist for planting. A simple soil temperature probe can help determine soil temperature at planting depth (Figure 1). Germination may be sporadic if cotton seed is planted into soil temperatures lower than 58 °F, and temperatures at or below 50 °F can cause imbibitional chilling. Imbibition, or the uptake of water through the seed coat, occurs within 24 to 48 hours after planting into moist conditions. Imbibitional chilling can damage the sensitive tip of the taproot or in severe cases kill the seed. Note that rainfall of 1 inch or more can drop soil temperatures by as much as 5 °F, so it is critical to pay close attention to soil temperatures and forecasted weather when considering planting cotton.
Plant when at least 5 days of warm weather are predicted. Cool air temperatures during the first 5 days after planting can delay germination, which may lead to reduced stands, increased risk of seedling diseases, and potential yield loss. Avoid planting when air temperatures are forecasted to be below 50 °F for any time during the first 5 days after planting.
Soil Preparation
Tillage systems affect how quickly soils warm up in the spring. Soils that have been conservation-tilled, like no-till and strip-till, typically warm more slowly than conventional-tilled soils. In no-till production, it is especially important to obtain a good stand on the first try for crop success. Seed should be planted shallow, 0.25 to 0.5 inches deep, into moisture, making sure the seed furrow is closed. Replanting cotton in no-till systems can complicate weed control and result in an uneven stand.
Soil warmth may also depend on soil characteristics: texture, color, moisture, and ground cover. Soils that are sandy or drain well warm up faster than heavy, water-logged soils. Darker soils and soils worked into a pre-plant bed prior to planting tend to warm up faster.
Soil crusting may prevent germinating seedlings from emerging. This is more common in compacted soils with low organic matter. A rotary hoe may be used to carefully loosen the soil surface. If soil crusting has occurred after planting or prior to emergence, hill dropping, or planting two to three seeds together, may also help seeds emerge.
Planter Preparation
Planter maintenance is important to increase planter accuracy, reduce time at planting, and increase planter longevity. The following parts should be checked, cleaned, and repaired or replaced if worn: drive trains, sprocket bearings, opener blades, shaft bearings, sprocket teeth, and double disc openers.
Checking the down pressure of the closing wheel will ensure good seed-to-soil contact for quick and even emergence. If soils are dry, increase down pressure to help bring water to the seed. If soils are wet, decrease down pressure to avoid soil compaction around the seed. If there is a vacuum metering system, clean it and check all seals. Calibrate the planter according to owner manual instructions. Follow appropriate planting speeds to maintain uniform planting.
Planter depth should be set in the field once the soil texture and moisture depth are determined. Planting too shallow will result in poor seed-to-soil contact and planting too deep can cause stand skips and delayed emergence. To determine actual planting depth and spacing, dig up the cotton seed behind the planter after planting 50 to 100 feet of row.
Planting Rate and Row Spacing
The optimal planting rate and plant population vary from field to field and are dependent on many factors, such as field and environmental conditions and row spacing. The Bayer Learning Center at Scott, Mississippi conducts trials to provide cotton growers with information on cotton agronomics. Check out the research report summaries at Scott Learning Center Research Reports for studies on row configuration and plant population.
Sources
Edmisten, K. 2018. Cotton seed quality and planting decisions. NC State Extension. 2018 Cotton Information. https://content.ces.ncsu.edu/
Boman, R., and Lemon, R. 2005. Soil temperatures for cotton planting. Texas A&M Cooperative Extension. SCS-2005-17. http://cotton.tamu.edu/
Kulkarni, S. Planter preparation, maintenance and calibration. University of Arkansas. FSA1047.
Robertson, W.C., and Roberts, B.A. Chapter 4 - Integrated Crop Management for Cotton Production in the 21st Century. 2010. In P.J. Wakelyn and M.R. Chaundry, (eds) Cotton: Technology for the 21st Century. International Cotton Advisory Committee. https://www.cotton.org/tech/ace/establishing-the-crop.cfm
Collins, G. 2016. Seedling vigor: Why is it important? NC State Extension. https://cotton.ces.ncsu.edu/.
Web sources verified 03/28/22. 1410_12659
