How to Grow Amorphophallus Konjac in Cold Climate
If you're looking for a truly unusual plant, amorphophallus konjac will fit the bill. The bulb will send out one huge leaf every year, and in three or four years, will develop enough energy to produce one huge, spectacular bloom. However, the beauty comes with a price, because the bloom has an odor that smells like rotting meat. Although it’s a tropical plant, amorphophallus konjac can easily be grown in containers in you live in a cold winter climate--if you can tolerate the stench.
Locate a very large container to plant the amorphophallus konjac bulb, and be sure it has a drainage hole in the bottom. Amorphophallus konjac will grow to be very large at maturity, so a 25- to 30-gallon container would be appropriate.
Fill the container with good quality commercial potting mix, and bury the amorphophallus konjac bulb at least 8 inches deep in the soil. Plant the bulb with the root end facing up. Amorphophallus konjac bulbs are different than most bulbs, because the roots grow from the top of the bulb rather than the bottom.
Avoid watering the Amorphophallus konjac bulb until you notice growth, which should appear in May or June. Once growth appears, keep the soil consistently moist throughout the growing season, and don't allow it to dry out between watering. Decrease watering when the foliage begins to shrivel and turn yellow in the fall
Fertilize with tomato fertilizer every week so the bulb will grow and develop the energy needed to produce a bloom. The larger the bulb, the larger the resulting bloom will be.
Move the container into a dry, cool place such as a garage or unheated storage for the winter months, but be sure the room won't freeze. Don't water the bulb while it's dormant. When the weather warms up in the spring, and you're sure that there is no longer any danger of freezing nights, move the container back outdoors.