The extra large bulb you get is similar to the 2nd image. 9/13cm Bulb
With indoor plants making a big wave, the big-leafed, the textured, and the variegated aroids take center stage. On the other end of the spectrum, a strange-looking plant that looks like a potato has gained stardom worldwide. It is the Stephania erecta.
Its popularity could be attributed to its striking peltate leaves and smooth huge globose tuber that makes it a conversation piece. Stephania erecta Craib (described by William Grant Craib with publication date of October 1922) is native to Thailand where it is found in thickets or forests with sparse vegetation. The soil in these central and northeastern regions where they abound are laterite or reddish in color due to ferric or aluminum oxide deposits. Natives gather them for their medicinal properties – to alleviate body aches and pains, and to relieve digestion problems among others. They can also be used as food on the table though we do not recommend that.
How to make them sprout
Stephania erecta tubers are sold as is, no roots, no leaves, just like potatoes. And the question I have been asked a hundred times is how to make them sprout. There is one simple answer: raise the humidity around the plant. How? A seed germination dome is perfect for sprouting multiple tubers all at the same time. An alternative is to place the potted plant inside an unsealed plastic bag. It is also wise to mist the twice a day.
The medium should be evenly moist, not wet or dry. It is best to error on the dry side. They should sprout in two (2) weeks or less. Like I always say, all plants are not created equal. Some are fast growers, some are slow…. just like people. I have had some the take up to 30 days to sprout.