Gossypium (genus, cotton, "Wata")

Japanese name: ワタ （綿）
Scientific name: Gossypium

[Overview]
A plant that yields cotton, with several lines of different origins.
The color of the fibers is white, but also brown, green and others.
It is a perennial, but because it is not cold hardy, it is treated as an annual in Japan.
The leaves are alternate, usually palmately 3–7-lobed, but may also be simple and unlobed.
The leaf margins are entire.
The flowers are hibiscus-like, 5-petaled, borne singly or several in the leaf axils, white to yellow, rarely reddish purple, with a dark flower base.
The staminal column does not protrude out of the flower, and the style does not branch.
The flowers open in the morning and wither by evening, lasting only one day.
The fruit is a capsule, and the surface of the seeds is densely covered with cotton fibers.

[Uses]
The fibers of the seeds are used as cotton.
An oil called edible oil is obtained from the seeds.

[Cultivation]
Propagate from seed.
Germination requires a temperature of 20–25 degrees, and growth also requires warmth, so sow in mid-May.
Germination is faster if the fibers are removed from the seeds and the seeds are scratched before sowing.
It dislikes transplanting, so either sow directly with plants spaced at least 30 cm apart and thin them out, or sow in plastic pots and then transplant.
It prefers a sunny, well-drained, airy, slightly alkaline soil.
Seedlings dislike excess moisture, so water thoroughly after the soil surface has dried; in midsummer during the flowering period, it is best to water every day at the cool times of morning and evening so that it does not dry out.
After the fruits have split open and the cotton fibers show, keep them away from rain and water.
If base fertilizer is applied, no further fertilizer is particularly necessary, but slow-release fertilizer may be given until before flowering, depending on growth.
Pinching in around July increases the number of branches and gives more flowers.
When the plant grows tall, set up stakes.
Pests include armyworms, leaf rollers and spider mites.

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