Sea island cotton

Gossypium barbadense

Tropical cotton species producing the longest, finest and silkiest cotton fibres in cultivation. The source of premium extra-long staple cottons including Sea Island, Pima, and Egyptian.

Hardiness ratings

Sea island cotton hardiness across the four zone systems
SystemRatingTemperature rangeHow to read it
USDA hardiness zone Zone 9–11 −6.7 °C to 10 °C Zones where it can be grown as an annual — not a frost-tolerance rating
RHS hardiness rating H2 1 °C to 5 °C Plant needs at least this level of cold tolerance
Canadian plant hardiness zone Zone 9 −1 °C and warmer Zones where it can be grown as an annual — not a frost-tolerance rating
Australian (ANBG) zone Zone 5–7 5 °C and warmer Zones where it can be grown as an annual — not a frost-tolerance rating

As a tender annual, Sea island cotton doesn't overwinter — the zone range shows where the growing season supports it. See the RHS rating for its actual cold tolerance.

Growing notes

  • Extra-long staple fibre (35–40 mm) produces the smoothest, strongest, finest cotton cloth — the premium of the cotton trade
  • Demands a longer, warmer and more humid growing season than upland cotton — historically grown on the Sea Islands of Georgia and the Carolinas, now mainly in Egypt, Pima country in Arizona, and parts of Peru
  • Heavier water demand than upland cotton
  • Yields significantly lower than upland cotton, but premium price compensates
  • Not reliably hardy outdoors in Canada — Canadian zone values shown represent the system maximum and do not imply garden cultivation north of the warmest coastal pockets.

Categories

Related plants

Cross-check Sea island cotton against your zones

Reference

Sea island cotton on Wikipedia