Thanks for sweet comments. Please watch a little animation with 2 roots [ame="http://www.youtube.com/watch?v=rpg8uvK0Jy0"]Root Growing 3D Animation - YouTube[/ame]
There are so many ways to get this done, correctly. Extrude along spline... Path Deform + Scale... Vertex animation... World space modifiers... Ivy Generator... RayFire... Thinking Particles... Grow1... Grow2... This is what you need to do, NOT scale. But I can see this might be a worthless post...