Amorphophallus declinatus Hett.

• Genus: Amorphophallus
• Botanical Background: Described by the botanist Hett in the late 20th century; named for its distinctive flower structure, which is characteristic of the Amorphophallus genus.

• Geographical Range: Primarily found in the tropical forests of Southeast Asia, especially in Malaysia and parts of Indonesia, where it thrives in lowland regions.
• Environment: Naturally grows in humid, tropical conditions with temperatures ranging from 25°C to 30°C; prefers well-drained, fertile soil and is typically found in shaded or partially shaded areas of rainforests.

Leaves

• Large, with a typical palmate structure and a deep green color
• Glossy, often reaching substantial sizes
• Leaf stalks are robust, supporting the broad leaflets, which have a distinctive, textured surface

Inflorescence (Spadix & Spathe)

• Large and imposing, with a characteristic mottled spathe that may range in color from green to purple
• Spadix is cream-colored and prominent, with a strong odor resembling decaying flesh, which attracts pollinators such as carrion beetles

Growth Habit

• Terrestrial and produces large, tuberous roots that support its growth
• Goes through an annual dormancy period where the above-ground structure dies back before sprouting again

Light Requirements

• Indirect, filtered light, mimicking the shaded forest floor environment
• Should not be exposed to direct sunlight for long periods

Watering & Humidity

• Plant requires regular watering, but care must be taken to ensure good drainage to prevent root rot
• Thrives in high humidity, ideally around 70% or higher

Soil & Potting Mix

• A well-draining, loamy potting mix with organic matter is best 
• Prefers slightly acidic to neutral soil (pH 6.0–7.0)

Temperature & Fertilizer

• Temperatures between 25°C and 30°C 
• Balanced, slow-release fertilizer can be applied every 4-6 weeks

Division and Stem Cuttings

• Propagation method is through division of the tubes
• Ensure each section has at least one viable growing eye

Seeds

• Less common due to the slow germination process and the challenges in pollination in non-native environments

Typical Issues

• Aphids, scale, and mealybugs
• Root rot

Treatment Recommendations

• Organic insecticidal soap or neem oil can be effective for pest control
  
• Ensure the plant is in well-drained soil
• Fungicides may be necessary for severe fungal infections
  

• Sometimes referred to as "the titan arum’s cousin" due to the similar structure of its inflorescence
• Large, smelly flower attracts carrion-feeding insects, contributing to pollination
• Due to its rare and striking appearance, it is valued by collectors of exotic plants and aroids
• Impressive flower and large leaves make it a stunning addition to any plant collection
  

Wild Population Status

• While not classified as endangered, Amorphophallus declinatus is vulnerable to habitat loss due to deforestation in its native range
• Conservation efforts are ongoing to protect the species and its habitat

Market Availability

• Available in specialty plant markets, but due to its specific growing conditions, it can be somewhat rare and expensive
• May find it in niche online plant stores or botanical gardens