Bidibid

Botanical name: Acaena fissistipula
Synonyms: None
Common name(s): Bidibid, Piripiri

About:
Acaena fissistipula is a fast-growing, low-growing native groundcover with attractive blue-grey foliage and a dense, compact spreading habit. It is closely related to Glaucous Bidibid (Acaena caesiiglauca) but generally forms tighter mats and is often faster growing.

Its colourful pinkish-red flower heads and decorative hooked seed heads make it both an attractive ornamental and a practical plant for erosion control and difficult sites.

Natural habitat:
Occurs naturally in montane to low alpine environments of the South Island. It is commonly found in tussock grasslands, open rocky places, stream margins, river terraces and other well-drained alpine habitats.

It thrives in exposed locations where competition from taller vegetation is limited.

Growing environment:
Performs well in full sun to partial shade and tolerates frost, drought, wind and free-draining soils.

In humid climates it grows best in open positions with good air circulation and soils that drain freely, avoiding prolonged winter wetness.

Endemic distribution:
Endemic to New Zealand’s South Island.

Height:
Approximately 10 cm

Width:
Typically spreads 50 cm to 1 m or more, forming dense mats

Flowering:
Summer (generally November–January)

Fruiting:
Summer through autumn

Uses:
• Native groundcover
• Bee food
• Riparian planting
• Erosion control
• Alpine gardens
• Rock gardens
• Dry bank stabilisation
• Low-maintenance landscaping

Appearance:
Growth habit:
A compact, mat-forming perennial that spreads by creeping stems, creating dense cushions of fine foliage across the ground.

Its tighter growth habit distinguishes it from many other bidibid species.

Stems:
Slender creeping stems spread across the soil surface and root where they touch the ground, allowing colonies to expand steadily.

Leaves:
Leaves are finely divided into numerous pinnate leaflets, giving the plant a delicate, feathery texture.

The foliage is blue-grey to grey-green and generally denser and finer than that of Acaena caesiiglauca, providing a soft, silvery appearance throughout the year.

Flowers:
Small flowers are grouped into rounded flower heads held just above the foliage.

The heads are green when young, maturing to attractive pinkish-red tones during summer.

Fruit:
After flowering, the heads develop into compact clusters of hooked burrs armed with fine barbed spines.

These persistent seed heads add ornamental interest and are characteristic of the genus.

Seeds:
The hooked fruits readily attach to fur, feathers and clothing, allowing effective dispersal across open habitats.

Ecology:
This species is well adapted to exposed alpine and montane environments where it helps bind loose soil and reduce erosion.

Its dense mats suppress weeds, conserve soil moisture and provide shelter for small insects and other invertebrates.

The flowers attract a variety of small pollinating insects, while the barbed fruits enable seeds to be transported by animals.

Associated habitats:
Montane and low alpine tussock grasslands, rocky outcrops, scree margins, river terraces, stream edges and open herbfields.

Associated species commonly include snow tussocks, Celmisia, Raoulia, alpine Coprosma, native grasses and other hardy alpine herbs.

How to grow:
Plant in full sun or partial shade in free-draining soil. Gravel gardens, rockeries, raised beds and dry slopes provide ideal growing conditions.

Water during establishment, but once established the plant is highly drought tolerant. Avoid heavy, poorly drained soils and humid, sheltered sites where prolonged moisture may encourage fungal problems.

Allow plants sufficient room to spread naturally or trim lightly to maintain neat edges.

Propagation:
Propagation is easy by fresh seed, division or rooted stem sections.

Established mats can be divided at almost any time during the growing season, and creeping stems that have rooted naturally establish quickly when replanted.

Fresh seed germinates readily when sown into a free-draining seed-raising mix and kept lightly moist.

Cultural use:
The Māori name piripiri refers to the hooked fruits that readily cling to clothing, feathers and animal fur.

Like other bidibids, the plant is recognised for its distinctive burrs, which are an effective natural seed dispersal mechanism.

Garden value:
Acaena fissistipula is an excellent native groundcover for alpine gardens, rockeries, retaining walls and dry banks. Its compact blue-grey foliage, colourful flower heads and dense spreading habit provide year-round texture and excellent weed suppression.

It is particularly valuable where a hardy, low-maintenance native groundcover is required for sunny, well-drained sites.