An exotic jungle has been discovered in an overgrown valley in Cornwall (report, November 27). Sub-tropical palms, shrubs and ferns were found growing in a gorge at Trebah Gardens near Falmouth, where they had remained hidden by later growth for more than a century.

These botanical wonders have thrived in the mild conditions of Cornwall. The maritime climate, warm breezes blown off the Gulf Stream and a sheltered location all help to protect the gardens from frost and severe cold.

A sub-tropical Mexican fuchsia shrub at Trebah caused great excitement when it flowered non-stop for a year.

A short way up the Cornish coast lies another surprise. The Tregothnan Estate, near Truro, has established the first commercial tea plantation in Britain. The climate there is remarkably similar to Darjeeling, averaging an annual 13.7C (56.7F) compared with Darjeeling’s 14.7C (58.5F). The tea bushes also thrive on rainfall averaging 940mm (37in) a year, although not quite the Indian monsoon that helps to soak the hills of Darjeeling with a yearly 3,037mm (120in).

Most crucially, the Tregothnan estate has no spring frosts, when the buds and young leaves of the tea bushes are most vulnerable. The plantation covers 20 acres of mature tea bushes that are harvested from April to October and produce a tea that is reckoned to almost match Darjeeling, although a lot more expensive.

Already, the Tregothnan plantation has attracted interest from elsewhere in Cornwall, and the hope is to form a UK tea growers association. Climate change could extend tea-growing to other areas in southern England.