Slender Forstera

Botanical name: Forstera tenella

Synonyms: Forstera bidwillii var. bidwillii; Forstera bidwillii var. densifolia; Forstera truncatella; Forstera major

Common name(s): Slender Forstera

About:
Slender Forstera is a delicate alpine and subalpine perennial that forms creeping mats of soft green foliage with elegant white flowers held on long slender stems. It is one of New Zealand’s most widespread members of the genus and is admired for its graceful appearance, making it an attractive choice for alpine gardens, rockeries and native plant collections.

Natural habitat:
Occurs in montane to alpine herbfields, seepages, damp turf, rocky slopes, open grasslands, stream margins and other cool, moist habitats.

Growing environment:
Frost, Sun, Part Shade, Moist & Free draining tolerant.

Endemic distribution:
Endemic to New Zealand.

Found throughout both the North and South Islands.

Height:
5–15 cm tall, with flowering stems reaching up to 15 cm

Width:
Forms creeping mats 30–80 cm or more across

Flowering:
December – February

Produces delicate white flowers, often marked with fine crimson speckles near the throat.

Fruiting:
January – March

Forms slender capsules containing numerous tiny winged seeds.

Uses:
• Alpine rock gardens
• Trough gardens
• Ground cover
• Native alpine collections
• Moist rockeries
• Ecological restoration of alpine habitats

Appearance:

Growth habit:
A creeping perennial with long rooting stems that spread across moist ground, producing upright leafy shoots and gradually forming loose mats.

Leaves:
Small elliptic to obovate leaves are arranged along the stems from closely overlapping to more openly spaced. The foliage is soft green, sometimes lightly flushed crimson, with entire margins and a neat, understated appearance.

Flowers:
Elegant six-petalled white flowers are carried singly or in small groups on slender stalks above the foliage. The petals usually display attractive crimson speckling near their bases with pale yellow nectar guides in the centre.

Fruit:
Produces narrow capsules that release numerous tiny winged seeds dispersed by wind.

Ecology:
Slender Forstera is a characteristic component of cool alpine and subalpine ecosystems where it colonises damp turf, rocky seepages and open herbfields. Its flowers provide nectar for small alpine insects while its creeping stems help stabilise shallow alpine soils.

Associated habitats:
Alpine herbfields, subalpine grasslands, seepages, stream margins, rocky bluffs, wet turf, fellfields and mountain meadows.

How to grow:
Grow in full sun or light shade in cool climates with consistently moist but well-drained soil. It performs best in alpine troughs, raised rock gardens and cool moist positions. Avoid hot, humid conditions and prolonged drying out.

Propagation:
Readily propagated from fresh seed or by dividing rooted creeping stems during spring or autumn. Plants establish best when kept cool and evenly moist.

Cultural use:
Although there are no recorded traditional Māori uses specific to this species, it is an important component of New Zealand’s native alpine flora and contributes to the biodiversity of mountain ecosystems.

Garden value:
An elegant alpine perennial prized for its delicate white flowers, creeping habit and attractive foliage. It is an excellent choice for rock gardens, alpine troughs and native alpine collections, where it combines beautifully with gentians, celmisias, hebes and other small alpine species.