Cotton is actually a perennial shrub, but growers often cultivate the plants as annuals. In Hawaii, the cotton plant, Gossypium tomentosum, or Ma’o in Hawaiian, is a perennial shrub lasting about 3-5 years, depending on growing conditions. This is not the commercial cotton that is grown in other parts of the world. (G. hirsutum is used in about 90% of the industry)
The native Hawaiian cotton, however, is used in breeding programs which has resulted in commercial hybrids which are less attractive to insect pests.
Maʻo can be
found growing in coastal plains and dry forests primarily on the leeward sides
of the main Hawaiian Islands. Ma’o naturally
grows in hot, dry, windy coastal areas tolerating the salty spray. Conversely,
it does not do well in locations with continuous high rainfall and in waterlogged
soil.
Periodic
pruning is necessary to control the height, to keep the shrub full and to prevent
low lying branches from spreading.
In 1838, a commercial cotton industry was actually started in Kailua on the Big Island.
Although it lasted for about a century, cotton never became an important trade
item. Even though the fibers were used by early Hawaiians for stuffing pillows,
the cotton was not used as a fabric. For
more information on Ma’o, see the website for native plants in Hawaii at http://nativeplants.hawaii.edu/plant/view/Gossypium_tomentosum
There is
also a CTAHR publication entitled, “Ma’o (Hawaiian Cotton).