Cotton, a natural fiber derived from the Gossypium plant, holds significant agricultural and economic importance worldwide. This leafy, green shrub, part of the mallow family, is cultivated across tropical and subtropical regions. The plant undergoes a series of distinct developmental stages, each contributing to the formation of the fibers used extensively in textiles and other industries.
The Square Stage
The initial reproductive structure of the cotton plant is known as a “square.” This term refers to the small, triangular floral bud enclosed by three protective leaf-like structures called bracts. Squares typically emerge on the plant approximately 30 to 40 days after planting, marking the beginning of the reproductive phase. As a square develops, it gradually increases in size, preparing for the eventual bloom. A young square might be only a few millimeters in diameter, growing to about 1 to 2 centimeters before flowering. The presence and health of these squares are indicators of the plant’s reproductive potential. This stage directly precedes the cotton flower, the next step in fiber development.
The Blooming Stage
Following the square stage, the cotton plant enters its blooming phase, characterized by the appearance of its delicate flowers. A cotton flower typically opens in the morning, displaying a creamy white or yellowish hue. These blossoms are relatively short-lived, usually lasting only for a single day. As the day progresses, the petals of the cotton flower change from their initial light color to a pink or reddish shade by late afternoon or evening. This color change signals pollination and fertilization, vital for the subsequent development of the cotton boll. After this single day, the flower withers and falls, leaving the fertilized ovary to transform into the cotton boll.
Boll Formation and Growth
Immediately after the cotton flower withers, the fertilized ovary develops into the cotton boll. This boll is the fruit of the cotton plant, housing the developing seeds and fibers. Initially, the boll appears as a small, green, immature structure. Over a period of approximately 50 to 80 days, the boll undergoes significant growth and maturation. During this time, the green boll expands in size, and the cotton fibers inside rapidly elongate and thicken.
Boll Opening
The final stage in the cotton plant’s reproductive cycle is the opening of the mature boll. Once fully developed, the green boll naturally begins to dry out, and the pressure created by the expanding fibers inside causes it to crack open. This splitting occurs along defined lines, revealing the fluffy white cotton fibers. The open boll exposes the mature cotton, which is now ready for harvest. The soft, white fibers, still attached to the seeds, create the familiar appearance of cotton in the field.