Could it be that you mean the VINE or even the PULSE, not the SKYLINE template? Because I really don't see anything that qualifies as "sprouting" in the Skyline template.
At least in the case of the Vine template, the growing effect is done with replicators and the Sequence Replicator behavior. Probably the best thing would be to dissect the project that is doing what you want to figure out how it is done and simply replicate or even just replace with your own graphics.
Or, even much more useful, check out Mark's training at Ripple Training. There is even one that deals specifically with replicators.