When it comes to selling sustainable products, research (see below) suggests that the rules are the same as for other goods: pick one message - the one that resonates most with consumers.
Our experience bears this, too.
A large, value-based retailer asked us to promote its impressive commitments to the environment. Message-testing showed that eco-friendly data points worked, but only when presented as part of a larger focus on consumer value, which consumers strongly associated with the brand.
An influential theory in social psychology holds that there are times when consumers are more likely to focus on a product’s immediate, concrete, lower-level benefits (“this product will save me money”) and other times when they will consider the product in terms of its long-term, abstract, higher-level benefits (“this product will help the environment”).