T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network


Polygala myrtifolia (Sweet pea shrub)

Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Fabales
Family: Polygalaceae
Genus: Polygala
Species: P. myrtifolia
Binomial name: Polygala myrtifolia
Common names: Sweet pea shrub, Sweet pea bush, Bellarine pea, Myrtle leaf milkwort, Parrot bush, Polygala,

Polygala myrtifolia is an evergreen 2-4m tall South African shrub. This fast growing, hardy plant is classed as a weed in New Zealand because it forms dense stands that smothers low growing plants. It produces many long lived seeds. It is found in coastal areas, forest margins, open land, islands and inland scrub. Found in poarts of the North Island but common from Auckland northwards. Found in Nelson in the South Island.

Polygala myrtifolia has thin, oval, leaves which are 25–50 mm long and up to 13 mm wide with a rounded tip. The leaves are arranged alternately and have entire margins. A form called Polygala myrtifolia 'Grandiflora' has longer, thinner, leaves and have pointed tips. 
The pink, crimson or white three petaled sweetpea like flowers (>17 mm long) and form all year round. They have a characteristic brush-like tuft protruding from the keel and they close at night.
The flat and heart-shaped seed capsules are 10 mm long. The seeds are hairy and dark brown (5 mm long) in colour.