Why Are My Galangal Leaves Curling?

Low humidity

Galangal prefers humidity above 60%, similar to ginger. In UK homes with central heating, winter humidity falls to 30 to 40%, causing the broad leaves to roll inward and the tips and margins to turn brown. The rolling is a water-conserving response and persists regardless of watering frequency when the air is too dry. Galangal plants in low humidity also grow more slowly, produce smaller leaves, and are more susceptible to spider mite.

What to do

• Stand the pot on a gravel tray with water. Mist the leaves with lukewarm water in the morning. Group with other tropical plants. Keep away from radiators and heating vents. A small humidifier placed near the plant provides the most consistent humidity increase.

Cold and draughts

Galangal is a tropical plant with no frost tolerance. It begins to show stress at temperatures below 15°C: the leaves curl at the tips, turn yellow and then brown at the margins, and growth stops. A cold draught from a window or door causes rapid tip browning. Galangal is more cold-sensitive than ginger and should be kept in a consistently warm position throughout the year in UK conditions.

What to do

• Maintain a minimum temperature of 15°C at all times; 18 to 25°C is ideal during the growing season. Move away from cold windows in autumn and winter. Keep in a heated greenhouse, conservatory, or warm room. Galangal does not need a dormancy period like ginger or turmeric and should be kept growing slowly in warmth over winter.

Drought and overwatering

Galangal needs consistently moist compost during the growing season. The leaves roll and droop rapidly when the pot dries out completely. However, galangal rhizomes rot if the compost is persistently waterlogged, particularly in cooler temperatures: signs of root rot include yellowing leaves, a mushy stem base, and foul-smelling compost.

What to do

• Water when the top 2 centimetres of compost are dry. Use a free-draining compost and ensure the pot has drainage holes. Reduce watering in winter when growth is slow. If root rot is present, unpot, remove rotted material with a sterile knife, dust cuts with sulphur, allow to dry briefly, and repot in fresh compost.

Spider mite and scale insects

Two-spotted spider mite colonises galangal in dry, warm conditions, causing pale stippling and fine webbing on the undersides of the leaves. Scale insects (soft scale or white waxy scale) may also appear on the stems and leaf undersides of galangal in a heated indoor environment, producing a sooty mould secondary infection from their honeydew excretions. Both pests are deterred by high humidity.

What to do

• Check leaf undersides and stems regularly. Treat spider mite with insecticidal soap, repeating every 5 to 7 days. Remove scale insects by wiping with a damp cloth or cotton bud dipped in diluted isopropyl alcohol. Raise humidity to deter both pests. Introduce predatory mites (Phytoseiulus persimilis) for spider mite in a greenhouse setting.

Frequently asked questions

Why are my galangal leaves curling?

Galangal (Alpinia galanga or Alpinia officinarum) leaves curl most commonly because of low humidity, cold temperatures, or drought. Galangal is a tropical rhizomatous plant closely related to ginger, native to the warm, humid regions of Southeast Asia. In UK cultivation as a container plant, the broad lanceolate leaves roll and curl when the air is too dry, temperatures fall below 15°C, or the compost dries out. Low humidity is the most common cause: UK homes in winter often drop to 30 to 40% relative humidity, well below the 60% or more that galangal prefers. Cold below 15°C causes the leaves to roll, yellow, and brown at the tips. Drought causes rapid leaf rolling that reverses once the plant is watered thoroughly.

How do I grow galangal in the UK?

Galangal (Alpinia galanga) can be grown in the UK as a container plant in a heated greenhouse, conservatory, or on a warm, bright windowsill. Start from a fresh galangal rhizome, available from specialist Asian food suppliers or tropical plant nurseries. Plant the rhizome horizontally 5 centimetres deep in a wide, shallow pot of moisture-retentive, free-draining compost (multipurpose compost with added perlite). Keep at a minimum of 20°C until shoots emerge (usually 3 to 6 weeks). Once growing actively, maintain warmth (18 to 25°C), high humidity (misting regularly or using a gravel tray with water), and consistent moisture. Feed every two weeks with a balanced liquid fertiliser from spring to late summer. Galangal can be placed outside on a sheltered, warm patio from June to September in most years. Bring indoors by September and keep frost-free through winter. Unlike ginger and turmeric, Alpinia galanga is an evergreen perennial that does not die back completely in winter in warm indoor conditions; it simply slows. Harvest rhizomes as needed by carefully removing sections from the edge of the clump without disturbing the whole plant.

What is the difference between galangal and ginger?

Galangal and ginger are both rhizomatous tropical plants in the Zingiberaceae family but they are different species with distinct flavour profiles. True ginger (Zingiber officinale) has a warm, spicy, slightly sweet flavour and is by far the more widely used in UK and European cooking. Greater galangal (Alpinia galanga) has a more complex, piney, citrusy, and medicinal flavour, used extensively in Southeast Asian cuisines (Thai, Indonesian, Malaysian, Cambodian) and much less common in UK supermarkets. Lesser galangal (Alpinia officinarum) is even more pungent and medicinal and is used in some herbal traditions. The plants look similar at a distance (large lanceolate leaves on a tall, leafy stem arising from a rhizome), but galangal plants are taller and more upright than ginger and have lighter-coloured, firmer rhizomes with a pronounced blue-grey tinge on the skin. Both can be grown in similar conditions in the UK.

Can galangal be grown from a supermarket rhizome?

Yes, galangal rhizomes purchased from an Asian supermarket or food shop can often be potted up and grown into full plants. Fresh galangal rhizomes with visible growth buds are most likely to sprout successfully. Plant in spring in warm conditions (minimum 20°C) and water sparingly until shoots appear. Galangal rhizomes from an Asian supermarket are the same species as those sold for growing (Alpinia galanga). Older or very dried rhizomes may not sprout reliably. The rhizomes are dense and firm (firmer than ginger), with a pale buff or blue-grey skin; choose the freshest-looking piece with prominent buds for the best results.