Leptinella squalida, commonly known as Brass Buttons

What Makes Leptinella squalida So Special?

Leptinella squalida is prized for its unique, fern-like foliage that forms a dense, low-growing mat. It is an excellent groundcover for small spaces, providing a fine-textured, almost mossy appearance. The "brass buttons" common name comes from its tiny, button-like flower heads, though the foliage is the main attraction. It is also remarkably tough and adaptable, tolerating foot traffic and a range of conditions once established.

Description and Details:

• Appearance: A low-growing, creeping, herbaceous perennial. Forms a dense mat.
• Flowers: Tiny, yellowish-green, button-like flower heads (capitula) that appear in late spring to early summer. The flowers are not particularly showy and are often considered secondary to the foliage.
• Foliage: Finely divided, fern-like leaves that are typically a grey-green to bronze-green color. The texture is soft and almost feathery. The leaves are arranged in a pinnate pattern (like a feather).
• Size: Grows only 1-2 inches tall and spreads indefinitely via creeping rhizomes. It can spread quite quickly under favorable conditions.
• Growth Habit: Mat-forming, spreading rapidly by rhizomes.
• Blooming Time: Late spring to early summer.

Native Habitat:

Leptinella squalida is native to New Zealand, where it grows in a variety of habitats, including coastal areas, grasslands, and subalpine regions. This wide range of native habitats contributes to its adaptability.

Landscaping Design Tips:

• Groundcover: Excellent for small areas, between stepping stones, in rock gardens, or as a lawn substitute in low-traffic areas.
• Stepping Stones: Perfect for planting between pavers or stepping stones, as it tolerates light foot traffic.
• Rock Gardens: Thrives in the well-drained conditions of rock gardens and complements the rocky aesthetic.
• Fairy Gardens: Its miniature scale makes it a popular choice for fairy gardens.
• Containers: Can be used in containers, either alone or as a "filler" or "spiller" element.
• Erosion Control: On gentle slopes, its dense mat can help prevent erosion.
• Lawn Substitute (with caveats): Can be used as a lawn substitute in areas with light foot traffic. It will not tolerate the same level of wear and tear as traditional turfgrass. It is best for areas that are primarily visual, with occasional walking.
• Companion Plants: Pairs well with:
  • Low-growing Sedums
  • Thyme (especially creeping varieties)
  • Scleranthus uniflorus (another New Zealand native with a similar mounding habit)
  • Small bulbs (like Crocus or miniature Daffodils) that will emerge through the foliage in spring.
  • Alpine plants.

Planting and Care:

• Sunlight: Prefers full sun to partial shade. In hot climates, afternoon shade is beneficial. In full shade, it may become leggy and less dense.
• Soil: Requires well-drained soil. It will not tolerate soggy conditions. Amend heavy clay soils with plenty of organic matter (compost, well-rotted manure) and grit (perlite, coarse sand) to improve drainage. A slightly acidic to neutral pH (6.0-7.0) is ideal.
• Watering: Water regularly, especially during establishment. Once established, it is moderately drought-tolerant, but it performs best with consistent moisture, especially in hot, dry climates. Allow the soil to dry out slightly between waterings.
• Fertilizing: Generally, does not require heavy feeding. A light application of a balanced, slow-release fertilizer in spring is usually sufficient. Avoid high-nitrogen fertilizers, which can promote excessive growth that is more susceptible to disease.
• Pruning: Minimal pruning is needed. You can trim back any runners that are spreading beyond the desired area. If the mat becomes overgrown or uneven, you can shear it back lightly.
• Winter Hardiness: Hardy in USDA zones 4-9. It is surprisingly cold-hardy.
• Propagation: Easily propagated by division in spring or fall. Simply dig up a section of the mat and separate it into smaller pieces, making sure each piece has roots.
• Mulch: Is not required but can be used.

Taxonomy:

• Kingdom: Plantae
• Division: Magnoliophyta
• Class: Magnoliopsida
• Order: Asterales
• Family: Asteraceae (Aster Family - Daisy Family)
• Genus: Leptinella
• Species: squalida

Morphology:

• Roots: Fibrous roots that develop from the creeping rhizomes.
• Stems: Creeping rhizomes that spread horizontally just below the soil surface.
• Leaves: Alternate, pinnately compound (divided like a feather), with very small leaflets. The leaves are typically grey-green to bronze-green.
• Flowers: Small, disc-shaped flower heads (capitula) that lack ray florets (the "petals" of a typical daisy). The flower heads are composed of tiny, yellowish-green disc florets.
• Fruit: Small, dry achenes (a type of dry fruit).

Popular Varieties:

• Leptinella squalida 'Platt's Black': The most popular cultivar, prized for its dark, almost black foliage. This provides a striking contrast to other plants. The flowers are also darker than the species.
• Leptinella minor: A very small species of Leptinella.
• Leptinella dioica: Another option with a great spreading habit.

Other Insights Gardeners Need to Know:

• Deer and Rabbit Resistance: Generally considered deer-resistant and rabbit-resistant.
• Pest and Disease Problems: Relatively pest-free and disease-resistant. Slugs and snails can sometimes be a problem, especially in moist conditions. Root rot can occur in poorly drained soil.
• Aggressiveness: Can be aggressive in ideal growing conditions, spreading rapidly via rhizomes. It can outcompete less vigorous plants. Consider this when choosing a planting location. It is best contained in a defined area (like between stepping stones) or used where its spreading habit is desired.
• Foot Traffic Tolerance: Tolerates light foot traffic, but not heavy, constant traffic. It is best for areas that are walked on occasionally.
• Maintenance: Generally low-maintenance, requiring minimal care once established.
• Allergen: Some people may experience skin irritation from contact with the plant.

Leptinella squalida, especially the 'Platt's Black' cultivar, is a valuable addition to gardens where a low-growing, fine-textured groundcover is desired. Its unique foliage, adaptability, and low maintenance make it a popular choice for a variety of landscape applications. However, be mindful of its spreading habit and choose a location where it can spread without overwhelming other plants.

Leptinella squalida 'Platt's Black', giving you the comprehensive gardener's guide you are looking for:

What Makes it So Special?

'Platt's Black' is prized for its unique, almost black, fern-like foliage that creates a striking contrast in the garden. It is a ground-hugging, mat-forming perennial that offers an unusual texture and color compared to typical green groundcovers. The tiny, button-like flowers are inconspicuous, but the foliage is the star of the show. It is particularly valued for its ability to tolerate some foot traffic, making it suitable for pathways and between stepping stones. It is deer resistant.

Description and Details:

• Appearance: Forms a dense, low-growing carpet of very finely divided, fern-like leaves. The color is a very dark bronze-green, appearing almost black, especially in full sun. The leaves are evergreen to semi-evergreen, depending on the climate.
• Size: Grows to only about 1-2 inches (2.5-5 cm) tall and spreads indefinitely via creeping rhizomes. A single plant can spread to about 12-18 inches (30-45 cm) wide over time.
• Flowers: Produces tiny, insignificant, yellowish-green button-like flowers in summer. These are often hidden amongst the foliage and are not a major ornamental feature.
• Texture: The foliage has a very fine, almost feathery texture, creating a soft, velvety appearance.
• Growth Rate: Moderate to fast spreading, especially in favorable conditions.

Native Habitat:

• Leptinella squalida, in general, is native to New Zealand. It is typically found in subalpine and montane regions, often in damp, open areas, grasslands, and along stream banks. This gives clues to its preferred growing conditions: cool, moist, and well-drained.

Landscaping Design Tips:

• Groundcover: Excellent as a groundcover in small areas, rock gardens, between stepping stones, or along pathways. The dark foliage provides a striking contrast to lighter-colored plants and stones.
• Rock Gardens: Perfectly suited for rock gardens, where it can creep over and around rocks, softening hard edges.
• Fairy Gardens: Its miniature size and unique texture make it a popular choice for fairy gardens.
• Containers: Can be used in containers, either alone or as a "spiller" plant, cascading over the edges.
• Contrast: Use it to contrast with plants with bold, large leaves or bright flowers. Silver, chartreuse, or gold foliage plants create particularly stunning combinations.
• Living Mulch: It can act as a living mulch around larger plants, suppressing weeds and helping to retain soil moisture (though it's not as effective as a thick layer of traditional mulch).
• Erosion Control: On gentle slopes, its spreading habit can help to stabilize the soil.
• Between pavers. It can withstand light foot traffic.

Planting and Care:

• Light: Prefers full sun to partial shade. The darkest foliage color develops in full sun, but it will tolerate some shade, especially in hotter climates. In deep shade, it will be greener and may become leggy.
• Soil: Requires well-drained soil. It thrives in moist, humus-rich soil but can tolerate a range of soil types, including sandy and clay soils, as long as they do not become waterlogged. Amend heavy clay soils with compost or other organic matter to improve drainage.
• Watering: Water regularly, especially during dry periods, to keep the soil consistently moist but not soggy. Established plants are somewhat drought-tolerant but perform best with consistent moisture.
• Fertilizing: Generally, does not require much fertilizer. A light application of a balanced, slow-release fertilizer in spring can be beneficial, but avoid over-fertilizing, which can lead to excessive growth and a loss of the compact form.
• Pruning: Pruning is rarely needed. You can trim back any unwanted spread with a sharp pair of scissors or a spade.
• Propagation: Easily propagated by division. Simply dig up a section of the plant and replant it in the desired location. This is best done in spring or early fall.
• Pests and Diseases: Relatively pest and disease-free. Slugs and snails may occasionally nibble on the foliage, but this is usually not a major problem. Root rot can occur in poorly drained soils.
• Winter Hardiness: Hardy in USDA zones 4-9. In colder zones, it may die back to the ground in winter but will usually regrow in spring.

Taxonomy:

• Kingdom: Plantae
• Phylum: Tracheophyta
• Class: Magnoliopsida
• Order: Asterales
• Family: Asteraceae (Daisy family)
• Genus: Leptinella
• Species: squalida
• Cultivar: 'Platt's Black'

Morphology:

• Leaves: Pinnately compound (fern-like), very finely divided, with numerous tiny leaflets. The leaves are arranged alternately along the stems.
• Stems: Creeping rhizomes that spread horizontally just below the soil surface.
• Roots: Fibrous root system.
• Flowers: Small, disc-shaped flower heads (capitula) composed of tiny florets.

Popular Varieties (and other Leptinella species):

While 'Platt's Black' is a very popular cultivar, there are other Leptinella species and cultivars to consider:

• Leptinella potentillina (syn. Cotula potentillina): Similar to L. squalida, but with slightly larger, greener leaves.
• Leptinella dioica: Another New Zealand native with green, fern-like foliage.
• Leptinella minor. A very small species.
• Leptinella 'Tiffindell Gold': A cultivar with bright yellow foliage. This provides a strong contrast to 'Platt's Black'.

Other Insights for Gardeners:

• Invasiveness: While Leptinella squalida spreads, it is not typically considered aggressively invasive in most garden settings. However, it can spread into lawns or other areas where it is not wanted, so be mindful of its placement. Regular edging can keep it in check.
• Foot Traffic: It can tolerate light foot traffic, but it is not as durable as some other groundcovers specifically bred for heavy traffic.
• Deer Resistance: Generally considered deer-resistant.
• Companion Plants: Good companion plants include:
• Sedum (Stonecrop)
• Thymus (Thyme)
• Armeria (Sea Thrift)
• Saxifraga
• Campanula
• Low-growing ornamental grasses
• Spring-blooming bulbs (the Leptinella will provide a nice backdrop after the bulbs have finished blooming)
• Mulching around plants. It is best to keep organic mulches like bark away from the crown of the plants.

By following these tips, you can successfully grow and enjoy the unique beauty of Leptinella squalida 'Platt's Black' in your garden. It is a rewarding plant that adds a touch of the unexpected to any landscape.