Giant taro

Sun

Partial shade or bright filtered light; tolerates more sun with ample moisture in humid climates. Protect from strong afternoon sun in hot, dry areas.

Water

Keep evenly moist during active growth, but do not leave roots in stagnant water. Water less in winter, especially when growth slows indoors.

Soil

Rich, moisture-retentive but well-drained soil with plenty of organic matter; slightly acidic to neutral is suitable.

Height

6-15 ft (1.8-4.6 m)

Spread

4-8 ft (1.2-2.4 m)

Foliage

Evergreen. Huge, glossy green, arrow-shaped leaves held mostly upright on stout stalks; individual leaves can reach 3-6 ft (0.9-1.8 m) long in tropical conditions.

Growth

Fast in warm, humid weather with regular water and feeding; much slower in cool conditions or containers.

Care needed

Medium

• Heat tolerant
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Needs looking after

Pick your zone, country, light and whether you have pets.

1. Planting day

   1.3 ft (0.38 m)

2. After 1 year

   4 ft (1.3 m)

3. After 2 years

   7 ft (2.3 m)

4. After 3 years

   10 ft (3.2 m)

   full size

About 3 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Toxic

Native to

Australia

Invasive in

the US

In the garden

Spreads vigorously: plan to contain it.

Growth rate

Moderate

• Plant after cold weather has passed, in a sheltered position protected from strong wind.
• Water deeply when the soil surface begins to dry; check containers frequently in hot weather.
• Apply a balanced liquid fertiliser monthly during active growth, following the label rate.
• Mulch the root zone to conserve moisture, keeping mulch clear of the stem.
• In cold climates, bring containers indoors before nights regularly fall below 50°F (10°C); give them bright light and reduce watering.

Pruning. Remove yellow, dead or badly torn leaves at the base of their stalks whenever needed, using clean secateurs and wearing gloves. Do not cut back healthy foliage routinely.

Spring

Repot crowded plants and separate rooted offsets as warmth returns.

Late spring

Move overwintered plants outdoors once nights stay above 50°F (10°C), gradually acclimatising them to brighter light.

Summer

Maintain even soil moisture and feed monthly while new leaves are developing.

Summer

Check leaf undersides for spider mites and inspect stems for scale and mealybugs.

Autumn

Move container plants under cover before cold nights; stop feeding as growth slows.

Winter

Keep sheltered plants bright and warm, watering sparingly without allowing the root ball to dry completely.

• Use as a large foliage focal point in a sheltered tropical border with gingers and cannas.
• Plant beside a pond, above the waterline in freely draining soil, for bold reflections and leaf contrast.
• Grow in a substantial container on a sheltered patio, allowing room for its wide leaves.
• Set against a plain wall or dark evergreen backdrop to emphasise the upright leaf shapes.

Garden styles it suits: Tropical, Modern tropical, Architectural minimal, Luxury resort, Balinese and Green on green.

Plant it with: Canna lilies, Shell ginger, Bird of paradise, Cast iron plant and Bird's nest fern.

Wildlife: Not a major nectar or seed plant for typical garden wildlife. Large leaves provide shelter for small animals in warm gardens.

• Spider mites cause pale stippling and fine webbing, especially indoors: rinse leaf undersides and apply insecticidal soap labelled for the plant if needed.
• Mealybugs and scale collect on stalks and leaf undersides: isolate affected pots, remove visible insects and treat with a suitable labelled product.
• Root or stem rot follows cold, waterlogged conditions: improve drainage, reduce winter watering and remove badly rotted plants.
• Cold, strong wind or sudden intense sun damages leaves: provide shelter, acclimatise plants gradually and remove damaged leaves once new growth resumes.

All parts contain irritating calcium oxalate crystals and are toxic to people, cats, dogs and horses if chewed or eaten. Exposure can cause intense mouth pain, drooling, vomiting and difficulty swallowing; severe swelling needs urgent medical or veterinary attention. Sap can irritate skin and eyes, so wear gloves when cutting or dividing. Do not eat garden-grown plants.

Where it spreads. Can spread by offsets and establish from discarded stem pieces in frost-free climates. It is invasive in Hawaii and is recorded as an environmental weed in parts of Queensland and New South Wales, Australia. Keep it out of waterways and natural vegetation, and do not dump garden waste.

• Taro (Colocasia esculenta)

  Taro usually holds its leaves downward, with the stalk attached to the underside inside the blade margin. Giant taro usually holds its leaves upright, with the stalk meeting the blade at the basal notch.

• Giant upright elephant ear (Alocasia odora)

  Usually smaller, with more rounded leaf lobes and some leaf tissue joining across the basal sinus near the stalk attachment. Giant taro generally has a deeper, more open basal notch;

• Giant elephant ear (Leucocasia gigantea)

  Typically has paler, often grey-green leaves and pale, waxy stalks. Giant taro usually has darker, glossier leaves and develops a more obvious upright trunk with age.

The epithet macrorrhizos means large-rooted, while giant taro refers to its size and resemblance to edible taro.

Propagation. Separate rooted offsets in spring or early summer, using a clean knife and retaining roots on each division. Pot into a free-draining mix and keep warm, lightly shaded and moist while new roots establish.

Accepted botanical name

Alocasia macrorrhizos

In the US and Canada

Introduced in Hawaii, the lower 48 states, Pacific Basin and Puerto Rico.

Native range

Bismarck Archipelago, Borneo, Maluku, New Guinea, Philippines, Queensland, Solomon Is. and Sulawesi.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.