Meanwhile I rembered that Valerian is used in Biodynamic farming: there is really something special about the plant... It is said that it has a warmth quality, which would "explain" why dilluted Valerian tea can prevent frost damage of plants, a few degrees under 0ºC. This warmth quality is further said to foster soil life and that is a reason why Valerian juice is used for the compost preparation, in such way it helps Phosphorous uptake.
At the Uni of Kassel they did an experiment, treating oat plants with higlhy dilluted Valerian juice and observed a decline in the amount of plants having leaf lice! The susceptibility to leaf-lice, they say, is related to the plants amino-acid metabolism, therefore the highly dilluted Varlerain juice has to have an effect on the amino-acid metabolism of plants. (details at http://www.agrar.uni-kassel.de/bdl/?language=en&c=49)
Who says we need synthetic pesticides?
Ah, yes, remember now: Monsanto says that.