You may plant your tuber when you receive it, but do not give it any water until September. Or you may store it in a paper bag in a cool spot until the Fall. When you see a wiry shoot emerge in the Fall, it is time to plant it (the shoot is the foliage, not the root).
A 1 gallon pot (4 liters) is a good size for 1 tuber, and 3 gallons will hold 3 tubers. For soil, use a well-draining mix. A typical mix is 2 parts potting soil to 1 part coarse horticultural sand and 1 part perlite. An alternate mix is 2 parts coir fiber to 3 parts perlite, with some slow-release fertilizer mixed in.
Plant the tuber 2 inches (5 cm) deep and sandwich it in 1/4 inch (6 mm) of perlite. In other words, put the tuber on a thin layer of perlite and lay some more perlite over the tuber, then continue filling the pot with soil.
In September, water the pot just enough so the soil is lightly moist throughout, and don't let it get any wetter until the leaves appear.
Once it sprouts, you may increase the watering. Give it sun, with some protection from hot afternoon sun.
2-3 weeks after the first shoot appears, feed with 1/4 strength fertilizer, and repeat every 4-6 weeks.
More information on the plant is here.
If you have any questions, please email me.
Enjoy your plant!
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