Family: Araceae
Scientific name: Amorphophallus gigas
Common name: Arum
Origin: Sumatra, Indonesia

This rare Amorphophallus species originates inthe lowland rainforests of Sumatra and produces a gigantic inflorescence, sometimes up to 3 meters tall. This makes it the tallest inflorescence in the world; officially taller than the more colossal inflorescence of the giant arum (Amorphophallus titanum). The umbrella-shaped leaves can reach a height of 4 meters in the rainforest, also downright spectacular. 
The plant grows from an underground tuber and produces 1 leaf at a time. When a leaf dies, it is succeeded by a new (usually larger) leaf. In dry periods, the plant may go dormant and temporarily survive only as a tuber. As a houseplant, this is usually during the winter months, but this can also happen during the rest of the year. After the dormant period, the tuber will sprout again, usually at a time the plant chooses itself and you have little influence on this. In the tropics the tuber can eventually reach a weight of 70 KG, but flowering can already occur from a weight of about 10 KG. 

In the living room it is a relatively easy plant to keep. A light position without direct sunlight is best, but the species can also grow in the shade. When the plant goes dormant, it is important to water less and keep the soil very slightly moist. In this way you can prevent the tuber from rotting. It is also possible to dig out the tuber during the dormant period and keep it in a damp place (e.g. a damp box) until growth starts again. During the growth period the soil can be kept well moist, but it is no problem if it gets dry for a while in between. 

The decorative leaves in particular make this arum a special houseplant. But once the tuber is big enough, you might be surprised by the spectacular flowering! 

Sowing directions: Seeds have a short shelf life. Sow directly in seed and cutting soil or a bag of moist Spaghnum moss. Keep the soil constantly slightly moist and allow to germinate at 25-30°C. 

Sowing time: Whole year
Difficulty: Intermedaite
Minimum temperature: 12 degrees Celsius

Photo 2: Jon Rambes