Baz; //What , yellow frost ?//
No, the frost has burnt the hedge, even my yew hedge is looking a bit yellow through frostbite, it will recover in the spring
Baz, With hedges & trees it isn't always the severity of the frost causing the sudden change in colour, it is the sudden contrast which can happen between mild & very cold temperatures.
The beautiful colours of trees in autumn are actually brought about by distress caused by the contrast between warm & cold temperatures.
At least that was how the magnificent colours of 'fall' in the Appalachians was described to me by a botanist type.