Titan Arum
Amorphophallus titanum
Amorphophallus titanum, commonly known as Titan Arum, is famous for its enormous inflorescence and unique odor. Native to the rainforests of Sumatra, this plant is a fascinating addition to any collection, attracting attention with its impressive size and unusual flowering behavior.
Everything it needs
9 essentials at a glance
Watering
Amorphophallus titanum prefers to be kept moist but not soggy.
Water thoroughly when the top inch of soil feels dry, typically every 1-2 weeks during the growing season. Reduce watering in the dormant phase, allowing the soil to dry out more between waterings. Signs of over-watering include yellowing leaves and root rot, while under-watering may cause wilting and browning leaf edges.
Light
This plant thrives in bright, indirect light but can tolerate partial shade.
Ideally, place it near a window where it can receive 6-8 hours of filtered sunlight daily. Avoid direct sunlight, which can scorch the leaves, and ensure it has some protection during the hottest part of the day.
Soil
Amorphophallus titanum prefers a well-draining potting mix, ideally a blend of peat, perlite, and orchid bark.
The pH should be slightly acidic to neutral, around 6.0 to 7.0. Good drainage is essential to prevent root rot, so ensure the pot has drainage holes.
Humidity
This plant enjoys high humidity levels, ideally around 60-80%.
To increase humidity, consider using a humidity tray, misting the leaves, or placing a humidifier nearby. Signs of humidity stress include browning leaf tips and edges, which indicate that the air is too dry.
Temperature
Amorphophallus titanum thrives in temperatures between 70-85°F (21-29°C) during the growing season and can tolerate down to 50°F (10°C) in dormancy.
It is best suited for USDA hardiness zones 10-12, as it cannot withstand frost and should be brought indoors in colder climates.
Fertilizing
Use a balanced liquid fertilizer with an NPK ratio of 10-10-10 or similar during the growing season, applying every 4-6 weeks.
Reduce fertilization during dormancy. Signs of nutrient deficiency include yellowing leaves and stunted growth, indicating a need for more nutrients.
Pruning
Pruning is minimal for Amorphophallus titanum.
Remove any dead or yellowing leaves as they appear to maintain plant health and aesthetics. Use clean, sharp scissors or pruning shears to avoid introducing disease. Deadheading is not applicable as this plant produces a single inflorescence.
Repotting
Repot every 2-3 years or when the tuber outgrows its pot, typically in spring.
Choose a pot that is 1-2 inches larger in diameter. Signs it needs repotting include roots growing out of the drainage holes or stunted growth. Carefully remove the plant, refresh the soil, and replant at the same depth.
Propagation
Propagation is typically done through offsets or tuber division.
The best time to propagate is during the dormant phase in late winter or early spring. Carefully remove the tuber from the soil, ensuring each division has roots and a growing point. Replant in fresh potting mix and water lightly until new growth appears.
When it's unhappy
Yellow leaves
Why it happens
Usually caused by over-watering or nutrient deficiency.
How to fix it
Check soil moisture and reduce watering if necessary. Fertilize with a balanced fertilizer to address nutrient issues.
Wilting leaves
Why it happens
Typically a sign of under-watering or low humidity.
How to fix it
Increase watering frequency and humidity levels to revive the plant.
Root rot
Why it happens
Caused by overly wet soil and poor drainage.
How to fix it
Remove the plant from its pot, trim away any rotten roots, and repot in fresh, well-draining soil.
Browning leaf tips
Why it happens
Often due to low humidity or inconsistent watering.
How to fix it
Increase humidity and ensure consistent watering practices to prevent further damage.
Pest infestations (e.g., aphids, spider mites)
Why it happens
Commonly attracted to stressed plants or those in low humidity.
How to fix it
Inspect the plant regularly and treat infestations with insecticidal soap or neem oil.
Care through the year
Spring
In spring, resume regular watering and fertilization as the plant emerges from dormancy. Monitor for new growth and adjust care accordingly.
Summer
During summer, maintain consistent moisture and high humidity. Fertilize every 4-6 weeks to support active growth and monitor for pests.
Fall
In fall, gradually reduce watering as the plant prepares for dormancy. Stop fertilizing and allow the leaves to die back naturally.
Winter
In winter, keep the plant in a cool, dry place with minimal watering. Allow the soil to dry out completely until spring.
Toxicity & Safety
Amorphophallus titanum is considered toxic if ingested, particularly the tuber. Symptoms of ingestion may include nausea, vomiting, and gastrointestinal distress. Keep out of reach of pets and children.
Good to know
Why are my Titan Arum leaves turning yellow?
Yellowing leaves on your Titan Arum can indicate over-watering or a nutrient deficiency. Check the soil moisture and adjust your watering schedule accordingly.
How often should I water my Amorphophallus titanum?
Water your Titan Arum every 1-2 weeks, allowing the top inch of soil to dry out between waterings. Adjust frequency based on humidity and temperature.
What kind of light does the Titan Arum need?
Amorphophallus titanum prefers bright, indirect light. Place it near a window with filtered sunlight for 6-8 hours daily to promote healthy growth.
How can I increase humidity for my Titan Arum?
To increase humidity, use a humidity tray, mist the leaves regularly, or place a humidifier nearby to create a more suitable environment for your plant.
When should I repot my Titan Arum?
Repot your Titan Arum every 2-3 years or when you notice roots growing out of the drainage holes. Spring is the best time to repot.
Is the Titan Arum toxic to pets?
Yes, Amorphophallus titanum is toxic if ingested, particularly the tuber. Keep it out of reach of pets and children to prevent any health issues.
How do I propagate Amorphophallus titanum?
Propagation is done through offsets or tuber division during the dormant phase. Carefully separate the tubers and replant them in fresh soil.
Grows well with
Track this plant in your garden.
Set care reminders, log growth, and join a community of plant lovers.