Kahili ginger

Perennial

Hedychium gardnerianum

Kahili ginger

Tall, lush ginger lily with heavily scented spikes of lemon-yellow flowers and red stamens late in summer.

  • Full sun, Partial shade
  • 1.5–2.5 m (5–8 ft)
  • 0.5–1 m (2–3 ft)
  • H2 · Zone 10
  • August–October
  • Deciduous
  • RHS Award of Garden Merit

Overview

Kahili ginger forms clumps of tall leafy stems with grey-green leaves, crowned late in the season by dense spikes of scented, lemon-yellow flowers with long red stamens. Orange seeds follow in split capsules.

It tolerates cold but not freezing in the RHS rating, around 1°C (34°F), though well-mulched rhizomes often survive brief frosts; US sources give USDA zones 7–10. It flowers best after long warm summers.

This is a serious invader of moist forest in New Zealand, Hawaii and other subtropical islands, so grow it only where it cannot spread.

At a Glance

Sun Full sun, Partial shade
Height 1.5–2.5 m (5–8 ft)
Spread 0.5–1 m (2–3 ft)
Hardiness H2 · Zone 10
Flowers August–October
Soil Chalk, Loam, Sand
Moisture Moist well drained
Habit Clumping, Upright
Water High
Maintenance Moderate

Growing Conditions

Min. Temperature 1°C (34°F)
pH Range 5.5–7.5
Fertility Fertile
Drainage Moderate

Aspect Suitability

  • East-facing
  • South-facing
  • West-facing

Soil Tolerance

  • Chalk
  • Sandy
  • Loam
  • Acid
  • Neutral pH
  • Alkaline

Foliage

Persistence Deciduous
Colour Grey-green
Leaf shape / texture lanceolate
  • Architectural foliage

Foliage interest: May–November

Seasonal Timeline

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Flowering
Foliage
Fruiting
Propagate
  • Flowering Aug Sep Oct
  • Foliage May Jun Jul Aug Sep Oct Nov
  • Fruiting Oct Nov
  • Propagate Apr May

How to propagate

One way to grow more Kahili ginger:

Division Apr Easy

You'll need: Spade or sharp knife

  1. Lift or expose the clump as growth starts
  2. Cut into sections, each with roots and healthy buds
  3. Replant at the same depth in improved soil
How long
1 hour
It's worked when
high
Then
Water in well and keep moist while new roots form.

Divide rhizomes in spring. Seed sown warm as soon as ripe; remove seed heads in high-risk regions instead.

Maintenance Calendar

  • Apr Divide congested rhizomes as shoots appear
  • May Feed and mulch with compost
  • Jul Keep soil moist through summer
  • Oct Cut off spent spikes before seed ripens
  • Nov Cut down blackened stems and mulch deeply or move pots under cover

Garden Design

Works well in: Tropical / Exotic

Tall grey-green stems topped with fragrant lemon spikes with red stamens late in the season. Best in a sheltered, warm border or large pot.

Companion planting: Bananas, Cannas, Colocasias, Tree ferns

Wildlife Value

  • Butterflies
  • Moths
  • Birds
  • Food source
  • Food

Food for birds: October–November

Safety

Not known to be toxic. One of the world's worst invasive plants in moist forest: banned from sale in New Zealand and invasive in Hawaii, the Azores, Réunion, South Africa and Jamaica. Do not plant in warm, wet climates near native forest, and cut off seed heads before the orange seeds ripen.