Here's one way of adding creepers/ivy using Woodland Scenics Foliage and Turf.
Before.
PVA added.
Foliage teezed to shape and pressed on after PVA has got tacky.
Tendril lines added with PVA.
Loose particles added and pressed on.
Darker coloured particles added here and there.
More tendrills added with deluted (Thinner) PVA and Turf (On a piece of paper) blown on with a straw, also lightly over the whole area.
Finished.