Amorphophallus hewittii is a distinctive tropical plant belonging to the Araceae family, which includes other “corpse flowers” like Amorphophallus titanum. This geophytic aroid is native to the rainforests of Borneo and other parts of Southeast Asia.
Understanding Amorphophallus hewittii’s Unique Lifecycle
The lifecycle of Amorphophallus hewittii begins with a dormant underground tuber that stores nutrients. After dormancy, the plant produces either a single, large, dissected leaf or, less commonly, an inflorescence. This impressive leaf, which can grow up to 2 meters across, often resembles a small tree with a thick stem and an umbrella-like canopy of divided foliage. It gathers energy and nutrients, storing them back into the tuber for the next growth cycle.
The most remarkable phase is the emergence of its inflorescence, a flower spike surrounded by a ruffled spathe. The spathe is typically green on the outside with a reddish-purple or maroon interior. Encased within the spathe is a tall, fleshy spadix, often lavender or pinkish-purple. This entire structure can reach an impressive height of 3-4 feet, sometimes up to 7-8 feet.
During its brief bloom, the inflorescence emits a strong, pungent odor mimicking rotting flesh. This scent attracts specific pollinators like flies and beetles by mimicking rotting flesh, thereby facilitating pollination. Flowering is rare and requires significant energy, typically occurring when the tuber is sufficiently large.
In its natural rainforest habitat, A. hewittii thrives in moist, shaded understories with rich, organic soil and consistently warm, humid conditions. Its rarity and specialized growth cycle make it a prized specimen for plant collectors.
Cultivating Amorphophallus hewittii
Successful cultivation of Amorphophallus hewittii involves replicating the warm, humid conditions of its native rainforest environment. A well-draining, rich, and airy substrate is essential for its potting medium. A suitable mix can include orchid bark, perlite, and rich compost or coir, ensuring proper drainage to prevent tuber rot.
A deep container is ideal to accommodate the plant’s large underground tuber and extensive root system. During the active growing season, Amorphophallus hewittii prefers bright, indirect light. Direct sunlight can scorch its leaves, so a spot near an east or north-facing window is often suitable indoors, or supplemental grow lights can be used. The plant generally thrives with 12-16 hours of light per day during its active phase.
Watering requires careful attention, with more water provided during active growth and significantly less, or none, during dormancy. During the active growing period, water thoroughly, allowing the top inch of soil to dry out between waterings. As the plant prepares for dormancy, signaled by the yellowing and decline of its leaf, watering should be gradually reduced. During dormancy, the tuber should be stored in a cool, dark place in dry or slightly moist substrate to prevent desiccation and rot. It is important not to overwater a dormant tuber, as this is a common cause of rot.
Optimal temperature ranges for A. hewittii are between 70–85°F (21–29°C), and high humidity, ideally above 60%, is necessary, especially during active growth. Indoor growers can use a humidifier or place the pot on a pebble tray with water. Fertilization should occur monthly during the growing season with a balanced, diluted liquid fertilizer, avoiding over-fertilization to prevent root damage.
Repotting is generally best done annually in spring as the tuber begins to emerge from dormancy. The new container should be about 2.5 times wider than the tuber. The tuber should be planted deep enough so that roots forming at the top are well covered. Handle the tuber carefully during transplanting to avoid bruising or nicking, which can lead to rot.
Propagating Amorphophallus hewittii
Propagating Amorphophallus hewittii is primarily achieved by separating offsets or “cormlets” that form on the main tuber. These smaller tubers develop alongside the parent and can be carefully detached during the plant’s dormant period. Once separated, these offsets can be individually potted in a well-draining growing medium, following the same cultivation guidelines as mature tubers.
While less common for the average grower, seed propagation is also possible. Amorphophallus hewittii seeds generally have a short viability period and should be sown as soon as possible after harvesting. Seeds are typically sown about 1 cm deep in a moist potting mix and require warm temperatures, around 25-30°C, for germination. Seedlings should be kept in warm, partially shaded conditions.
Addressing Cultivation Challenges
Tuber rot is a common and significant problem when cultivating Amorphophallus hewittii. This condition often results from overwatering, especially during dormancy, or from using a poorly draining soil mix. To prevent rot, ensure the potting medium is well-drained and avoid leaving the tuber in consistently wet conditions. If rot is detected, carefully cut away affected parts, dust healthy tissue with fungicide or cinnamon powder, and allow it to air dry before repotting in fresh, dry soil.
Pests like spider mites and mealybugs can affect A. hewittii. Inspect the plant regularly for early detection. Use insecticidal soap sprays or chemical treatments if infestations become problematic.
A lack of growth or failure to bloom can be frustrating. Insufficient light is a common reason for stunted growth, as the plant needs bright, indirect light to photosynthesize effectively and build energy reserves in its tuber. Improper dormancy, such as not allowing a sufficient rest period or keeping the tuber too wet, can also hinder future growth and blooming. Immature tubers are another factor; A. hewittii typically needs to reach a substantial size before it can produce an inflorescence.
Leaf issues like yellowing or browning leaves often indicate specific care deficiencies. Yellowing leaves can signal overwatering or nutrient deficiencies, while browning leaf edges may point to low humidity or scorching from direct sunlight. Adjusting watering practices, providing appropriate humidity, and ensuring proper light exposure are essential to maintaining healthy foliage. Note that yellowing and wilting are normal as the plant enters dormancy.