Narrow leaved plantain is a particularly useful source of Selenium and naturally occurs in the UK. Performance is best in low fertility and drought prone soils where it can last for many years. It does not always thrive on moist fertile sites. Boston is a new variety developed in New Zealand from hardy plants found in N. Germany. It is significantly higher yielding than Tonic, the main variety used in the UK. It also remains much leafier because it flowers 25–28 day later.