Prasophyllum spp.

leek orchid

Attracts Pollinators Fragrant (moderate)Container Friendly

SunFull Sun – Part Shade

WaterLow

HardinessZones 8–10

Overview

Prasophyllum spp. is a large genus of terrestrial orchids, the leek orchids, with around 140 species native to Australia and New Zealand. Each plant grows from an underground tuber and produces a single hollow, cylindrical leaf that resembles a chive or leek and sheathes the flowering stem. The slender spike, 6-32 in (15-80 cm) tall depending on species, carries from a few to many small flowers that are non-resupinate, so the lip sits uppermost rather than below. Flower colour ranges through green, yellow-green, brown, purple, and white, and many species are sweetly fragrant, especially in warm sun. Plants are dormant as tubers through the unfavourable season and reappear after autumn or winter rain. Flowering in many species is strongly promoted by summer fire. The genus depends on soil fungi and specific insect pollinators, which makes most species difficult to cultivate, and a further limitation is that many are rare, localised, or legally protected in the wild.

Native Range

Prasophyllum spp. is native to Australia, where it occurs in every state and is most diverse in the south and east, and to New Zealand. Plants grow in grassland, grassy woodland, heath, and montane herbfields, usually in seasonally moist, well-drained soils.

Suggested Uses

Grown mainly by specialist terrestrial-orchid growers and in botanical and conservation collections, in deep pots under cool glass. A few robust species are used in native grassland restoration. Plants are valued for their fragrance and botanical interest rather than for garden display.

How to Identify

Identify Prasophyllum spp. by its single hollow, onion-like leaf that wraps the stem, with the flower spike emerging through a slit in the leaf. The many small flowers are held with the lip uppermost, the reverse of most orchids. A sweet scent in sunshine and a grassland or heath habitat are further pointers.

Appearance

Size & Dimensions

Height6" - 2'8"

Width/Spread2" - 6"

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~4 weeks

Winter Spring Summer

Flowering varies with species and region, spanning late winter, spring, and early summer, broadly August to January. The small, often fragrant flowers open in sequence up the spike over two to four weeks. In many species flowering is sparse except in the season after a summer fire.

Detailed Descriptions

Flower Description

green, brown, purple, or white

Foliage Description

green

Growing Conditions

Sun Requirements

SunFull Sun SunPartial Shade

Requires 4-9 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range5.0 - 7.0(Neutral)

357912

Soil Types

sand loam

Drainagewell drained

Water & Climate

Water Needs

Low

Frost Tolerance

hardy

Time to Maturity

3-5 years from seed to flowering

Care & Maintenance

Care Guide

Prasophyllum spp. grows in full sun to light shade in seasonally moist but well-drained, low-nutrient soils at an acidic to neutral pH of about 5.0 to 7.0. The tubers need a dry or cool dormant period, and waterlogging during dormancy rots them. Growth depends on a partnership with specific soil fungi, so plants resist ordinary cultivation and are rarely moved successfully from the wild. Where grown, they are kept in deep pots of free-draining mix and watered only during the growing season. Most species tolerate light frost and suit cool to warm temperate climates around USDA zones 8 to 10. Collection from the wild is restricted, as many species are threatened.

Pruning

No pruning is required. The single leaf and spent flower spike are left to die down naturally as the plant returns to dormancy, feeding the tuber for the next season. Seed capsules can be removed or left to ripen.