I've got a little container that looks just like this except mine are a little older and have started growing hairlike thorns out of the top. Its fun watching them grow, although slowly. Mine like to change colors from green to pink and back
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Obliguhl, you might have to put them in more light, it didn't take but five days or so for most of mine to pop up but I took them out from under the florescent and placed them in the windowsill and about a month after the first ones popped up I am still getting new ones here and there.
'Little spider weaves a wispy web, stumblin' through the woods it catches to my head. She crawls behind my ear and whispers secrets. Dragonfly whiz by and sings now teach it.'