Will Royal Grass® artificial grass stay green? Royal Grass® is made with colouring agents and UV stabilizers of the highest quality. This means that UV radiation has no effect on the colour of the grass. No matter how much sun, rain, hail, or snow your artificial grass lawn has to endure, it will say green and remain looking attractive; the colour of your artificial grass will not fade. We have tested our artificial grass on colour fastness and UV resistance under extreme circumstances. From the hot deserts of Arizona, to the humid conditions of Florida, our artificial grass has proven its worth. Thanks to 35 years of extensive research on the UV resistance of grass fibres under highly demanding circumstances, such as intensive sports use, Royal Grass® feels confident enough to offer a warranty of 11 years on colour fastness for all types of artificial turf.