Colour plays an important role in user experience. Your choice of colour not only shapes your brand or product's identity, it can also affect how users engage on a subconscious level, meaning you can use colour to inspire certain emotions in your users.
For instance, red is associated with passion and intensity and orange is associated with warmth. Both Holiday Inn and Greenpeace use green as the primary brand colour, although their brand positioning is very different. This is because green colour is associated with growth, environment, relaxation. Therefore, collaborate with the creative designers in determining the look and feel of your website to ensure the colours are inline with the user experience you want to deliver. Finally, be careful when designing websites for different cultures since the meaning associated with colour can change across cultures.