Cotton remains a major commodity in Tennessee agriculture, particularly in the western regions where the soil and climate are favorable for its cultivation. Successful production relies heavily on precise timing throughout the growing season. Knowing when to plant, nurture, and harvest is fundamental to maximizing both yield and quality. The final harvest window is a culmination of months of growth, dictated by the plant’s biology and local weather patterns.
The Cotton Growing Cycle in Tennessee
The cotton season begins in late spring. The optimal planting window falls between April 20 and May 10, when soil temperatures are reliably warm enough for germination. The minimum soil temperature for planting is around 65 degrees Fahrenheit, needed for a strong, uniform stand of seedlings. Plants then enter the vegetative stage before moving into the reproductive phases.
These stages begin with squaring (formation of flower buds), followed by the bloom, which typically occurs in July and August. After the flower drops, the protective casing around the developing fibers, known as the boll, begins to form. A single boll takes 50 to 60 days to mature.
Harvest timing depends on when these bolls naturally crack open, exposing the white lint. The goal is for a high percentage of bolls to be open before the first significant frost. Cotton generally requires 150 to 180 days from planting to reach harvest maturity.
Critical Timing When Harvesting Begins
The primary cotton harvest window in Tennessee typically opens in late September and extends through December. While some crops may be ready for picking early, the bulk of the activity occurs throughout October and November. This period is a race against unpredictable fall weather, which significantly influences the quality of the exposed lint.
The decision to begin harvesting is based on the percentage of open bolls in the field, with growers aiming for 60 to 75 percent open bolls. Prolonged dry periods are necessary for the lint to dry out and for heavy machinery to move through the fields without damaging the crop or compacting the soil.
A hard, killing frost can assist the process by naturally dropping the remaining leaves. However, an early frost can damage immature bolls and reduce fiber quality. The harvest often occurs in multiple rounds, or “once-over” picking, followed by a potential second pass. Waiting too long risks weather damage, which stains the cotton and reduces its market value.
Preparing the Crop for Harvest
Before mechanical pickers enter the fields, farmers must execute defoliation: the application of chemicals to cause the cotton leaves to drop. The purpose of defoliation is to remove foliage that would contaminate the lint, resulting in cleaner, higher-quality cotton fiber. This step also allows sunlight and air to reach the lower bolls, encouraging them to open uniformly.
The timing of the chemical application is determined by the crop’s maturity, often assessed using metrics like the number of nodes above the cracked boll. Warm, sunny weather with evening temperatures above 60 degrees Fahrenheit is ideal for the defoliant chemicals to work effectively.
Applying chemicals too early can reduce the final yield and the fiber’s micronaire (a measure of fineness and maturity). Applying them too late can delay the harvest and expose the crop to poor weather.
From Field to Fiber
Once harvested, the seed cotton is transported to a facility called a gin. Ginning separates the cotton lint (fiber) from the seeds and removes any remaining trash and stems. The modern process begins with the harvested material being fed into the gin, often after being dried to remove excess moisture.
Inside the gin stand, circular saws pluck the lint away from the seeds. The seeds, a valuable byproduct used for oil and livestock feed, are collected separately.
The cleaned lint is then compressed into dense, standardized blocks known as bales, which typically weigh around 500 pounds each. These bales are ready for storage and transport to textile mills to be spun into yarn.