Cotton fabric doesn't just spring from the ground fully formed -- a lot of work is involved before you ever see a bolt of it at the craft store. The process leading up to the finished fabric we all know so well involves growing the cotton from seeds, processing the raw fibers and eventually processing the fibers into cloth.
From the Ground Up
Cotton cloth starts off as a seed, planted either by hand or by machine. After about three months, the cotton plants produce flowers, which live only for three days. They then die and are replaced with seedpods called cotton bolls. The bolls contain approximately 30 seeds each, and over the course of several months, moist and dense fibers form around them. When the bolls are mature (usually around the time the cotton plants have reached 4 feet in height), the bolls open, revealing the approximately 500,000 fluffy, white fibers contained inside.
Picking and Processing
Cotton can be picked one of several ways. Sometimes the fibers are removed by hand, in a long, laborious process. Other times, machines are used. There are two general mechanical harvesters used to pick cotton bolls. Strippers comb the plants and pick both opened and unopened cotton bolls. Pickers utilize a rotating spindle-like contraption to pick up the sticky fibers from only the open bolls.
From Plant to Fiber
The plant fibers harvested from the bolls are taken to a factory called a ginnery. They're removed from the seeds via a cotton gin. Leaves, branches, field dirt and other debris are also removed. A separate machine cleans and dries the cotton fibers, which are then pressed into large bales weighing up to 500 pounds each. The bales are secured with steel bands and loaded up to be shipped to mills, where they will be processed into yarn or thread, and eventually cotton cloth.
From Fiber to Cloth
At the mills, the cotton bales are broken open and processed by carding and combing. Carding untangles the fibers while combing removes shorter fibers and ensures all fibers are aligned in the same direction. The fibers are twisted together to make a stronger strand called roving. The roving is then spun by machine or hand into yarn or thread. The yarn or thread can be subjected to a number of finishing techniques to bleach or dye it, or to make it wrinkle resistant or waterproof. Finished yarn or thread is then woven or knit into cotton cloth. The finished cloth can also be subjected to mechanical manipulation to either preshrink or prestretch the fabric.