Southern Brass Buttons (Cotula australis)

Plant Snapshot

Common Name: Southern Brass Buttons
Latin Name: Cotula australis
Alternate Names: Brass buttons
Hardiness Zones: Tends to persist in mild frost free climates and die back in severe frost.
Typical Height: 0.5–3 in (1–8 cm) above ground.
Typical Spread: Forms mats 1–3 ft (30–90 cm) or more across where established.
Bloom Period: Spring to summer in many climates. May flower for extended periods in mild areas.
Soil Preferences: Prefers moist, well drained to seasonally damp soils but tolerates poor, sandy and compacted soils. Avoid permanently waterlogged heavy clay.
Light Preferences: Full sun to part shade. Flowers best in sunnier sites but tolerates light shade.
Toxicity: No consistent authoritative reports of severe toxicity to pets found. Some Cotula species can cause skin irritation in sensitive people and ingestion may cause mild stomach upset. Verify with local poison control for safety guidance.
Propagation: Propagate by seed or by division and by allowing creeping stems to root. Surface sow seeds and keep moist until established.

Key Facts

Low growing mat forming groundcover.
Produces small yellow button like flower heads.
Spreads by seed and by creeping stems or stolons.
Tolerates a wide range of soils including poor and compacted soils.
Does well in full sun and part shade.
Used between pavers, in rock gardens and as a lawn alternative.
Persistent in mild climates and can die back in hard frost.
Generally low maintenance once established.

Southern Brass Buttons is a low growing mat forming groundcover that bears small yellow button flowers and suits rock gardens, paver joints and low traffic lawn replacements. It spreads by seed and creeping stems and persists best in mild climates while it can die back after hard frost.

Identification

This plant forms a tight carpet 1 to 3 feet across and stays very short at about 0.5 to 3 inches high. Leaves are small and close to the ground and the plant produces tiny yellow button like flower heads that sit on short stalks above the mat.

Where to grow and common uses

Plant in full sun to part shade where a low maintenance groundcover is needed. It tolerates poor and compacted soils and performs well between pavers, in rock gardens and as a low traffic lawn alternative. Avoid sites that stay permanently waterlogged.

Planting and timing

Establish from surface sown seed or from small divisions and rooted creeping stems. Sow seeds on the soil surface and keep them moist until they root. Plant divisions or plugs into prepared soil and firm in place so stems can root and spread across the surface.

Watering and soil care

Plants prefer moist well drained to seasonally damp soils but tolerate poor sandy and compacted ground. Excessive wetness leads to rot and poor health so do not plant in heavy waterlogged clay. Flowers are more abundant in sunnier sites while light shade is tolerated.

After flowering and maintenance

Trim or mow lightly to tidy spent flower heads and to limit seed set if spread needs control. Divide overcrowded mats to rejuvenate growth and relocate pieces to fill bare patches. In colder conditions the mat may die back and then regrow from surviving stems or seed in milder weather.

Spread, naturalizing and control

Southern Brass Buttons spreads both by seed and by creeping stems or stolons and can form extensive carpets in favorable mild climates. To control spread remove flower heads before seed sets, lift and divide to thin mats or provide edging to limit runner colonization into adjacent beds.

Containers and hardscape use

Use in shallow troughs, between pavers and in rock garden pockets where a very low ground layer is wanted. In containers avoid heavy watering and choose a free draining mix so roots do not sit in water. Small plugs will quickly root into crevices and shallow soil.

Frequently asked questions

How fast does Southern Brass Buttons grow?: Growth rate varies with light moisture and temperature but plants can form a 1 to 3 foot mat over a season or two in favorable mild conditions by seeding and rooting of creeping stems.
When does it flower?: Flowering generally occurs in the warmer part of the year and often in spring to summer. Exact timing varies with local climate and hemisphere.
Is it suitable as a lawn alternative?: Yes for low traffic areas. It tolerates compacted and poor soils and creates a low carpet but avoid high wear sites and places that stay waterlogged.
How do I propagate it?: Propagate by surface sowing seed or by division and by using creeping stems that root. Keep surface sown seed moist until established.
Is it invasive or hard to control?: It can naturalize and spread by seed and stolons in mild climates. Control by removing flower heads, dividing mats and installing physical edging to stop runners.