The sticker that nudges environmentally-friendly weed control

What unsustainable behavior needs to change:

Herbicides and Pesticides are harmful for the environment, the animals and humans in it. An initiative by the Dutch Ministry of Infrastructure and Water Management to reduce the use of pesticides was unfortunately not successful – people just switched to kitchen remedies and organic acids, such as vinegar. As it turns out, many people do not know that using vinegar can still be harmful for the biosphere – ideally weeds and pests should be removed manually or with hot water. This is especially true for driveways or hard paths in the garden, where the herbicides are most often applied.

A study by Dutch behavioural consultancy Dijksterhuis & Van Baaren examined the factors playing into the use of vinegar as herbicide and tested nudges and communication formats to make people shift to the less harmful behaviour. 

As it turns out, what makes people use vinegar is not so much the health and sustainability aspect, but the fact that they did not know it was harmful. Also vinegar appeals to people, because it is: 

• cheap,
• convenient,
• effective and
• available everywhere 

Therefore, the alternative behaviour presented to the vinegar users, needed to fulfil the same criteria. They identified that using boiling water from the kettle fulfilled all of those criteria and was therefore chosen as the key behaviour. Vinegar users were also found to be significantly more ashamed of an untidy garden than non-vinegar users – so communication around the nudge played on that feeling. Lastly, to change behaviour, the nudge needed to break a habit – because weed control and the way it’s done is a habitual behaviour.

The Green Nudge:

A sticker on a kettle reminding people to use boiled water as an herbicide promises to be the most effective nudge. First of all, it reminds people at the right time and location – where the behaviour should occur. Secondly, it guides them to the desired behaviour, without much explanation. The sticker can be sent with additional information in the mail at a low cost; while a selection of 3 different designs for the stickers increases the likelihood that people will be willing to place the sticker on the kettle. 

Rolling out this campaign under the Dutch Ministry of Infrastructure and Water Management would greatly increase its chances of success compared to the original initiative.

More information on the survey, the identified target groups and alternative examined nudges can be found here (for Dutch readers).