Hebe armstrongii is an erect growing whipcord, growing to 2 ft (60 cm) high, with slender upright branches. The flowers are white, and are in terminal spikes, early summer – although it tends to be shy-flowering. Hardy in the UK.
This hebe was found by J F Armstrong in 1869, near the source of the Rangitata River, Canterbury, South Island, New Zealand. It is now seen near Poulter Hill, Esk River, and Castle Hill, east Canterbury. Hebe armstrongii is closely related to Hebe annulata and Hebe salicornioides.