Cotton is grown commercially as an annual shrub and reaches about 1.2 metres in height. Its leaves are broad and heart-shaped with coarse v eins and three to five lobes. The plant has many branches, with one main central stem. The cotton plant’s taproot reaches a depth of 1.5 metres.
Squares (flower buds) develop several weeks after the plant starts to grow, with flowers appearing a few weeks later. The flowers then drop, leaving a ripening seed pod that becomes the cotton boll (the fruit) after pollination.
The plant also produces seeds that are contained in small capsules surrounded by fibre in the cotton bolls.
Each cotton boll usually contains 27-45 seeds, and attached to each seed is between 10,000 – 20,000 tiny fibres about 28mm in length.
Cotton fibre is made from cellulose, has a slim coating of wax and is thin and hollow like a straw.
When mature, the crop is picked and ginned, a process that separates the cotton fibre (or lint) from the seed.
Cotton lint makes up about 42% of the picked cotton by weight and contributes about 85% of the total income from a cotton crop. The other 15% of the income comes from cottonseed.
