I think some people also use water crystals or water beads for rooting cuttings, especially anything that's prone to rotting before it gets roots (with water beads, the cutting gets moisture but still gets some air)...
That's a great price for the round beads! I've seen them on ETSY for $2-6 for ONE 14 gram packet. And this is about a pound of beads, if I did my math right. I get polymer water crystals (not the pretty round ones) in bulk now, but the first time I used them I paid nearly $10 for a 12 oz container of "Soil Moist" crystals.
Hmm...
