I intend to grow a wild Fig tree (Indian) from a cutting I broke off the foot path. Will it sprout roots faster in water or should I pot it and hope? The Pipal cutting has both root buds and branch sprouting.
We tried rooting a rubber plant, which is technically a fig, in water once. It didn't work (the cutting was in the water, and alive, for a super long time, too, but it never got any roots). So, if you're left between those two choices, I would go with the soil. Soil generally works better and faster for rooting cuttings anyway, though (as long as it's a new, suitable seed-starting mix or something, and you keep it out of bright light for a while). Figs might take a different process than say tomatoes or watermelon, however.
How fast the roots sprout isn't necessarily the important thing, though. The important thing is whether it will live and grow after it sprouts roots and is transplanted. I've found that even when cuttings grow roots in water, they're still susceptible to damping off after you transplant them. So, if soil will rot a cutting being rooted in it, it can also rot a cutting with roots transplanted into it. I've found that using 2700k CFLs by the plant can stop damping off from happening, however, as can strong south window sunlight.
Also, plants rooted in water can become depleted of nutrients if it takes them very long to root. The main advantage of water (other than that you can see the roots form) seems to be that sun doesn't damage the cuttings as much the first few days.
I've never tried such with bonsai, but I found this article (with images) on how to root a ficus cutting.
It describes trimming the cutting to the desired form first, then planting it in a highly aerated medium so the cutting is above the water. Then place this in a highly humid environment and lots good indirect sunlight.