Wheatpaste is liquid adhesive that is made from flour and water and some glue. It has been used for many different applications in history. Some different examples are bookbinding, paper mache, flyposting, collage work, and decoupage. Since the 19th century people have been using it for hanging flyers or advertisements. Such as circus bills and commercial posters. Infact most poster hangers used to create their own pastes up until the end of the 20th century when pre-made mixes were distributed.
The difference between different pastes depends on what type of glue is used or if you are using flour or starch. The gluten in the starch will make it harder for the paper to come down over time. It is important to adhere to the right surface as well, wheatpaste tends to stick to concrete or metal much better than to wood or plastic. All of these things need to be taken into consideration when baking and applying your wheatpaste.
There are different ways to apply a poster or stencil. Depending on the size of the design and the paper weight you might want to have a brush handy. You can start from the bottom with a group of people and flatten the design down with the paste and work your way up, eventually making it flat and stuck to the wall, and then going over the front and edges one more time to make sure that it is applied. If you are using newsprint or cheap rough paper, you can briefly dip the paper in the paste and stick it to the wall or surface like a sticker essentially.
Measurements and materials are very important for the process as well. Depending on what type of flour or starch will determine how strong the paste is. If there is too much water then it won’t be sticky at all. If the paste is sitting too long in the pot while being made it will get clumpy and unuseful. If the wheat paste is not secured in an airtight container after the cooking then it will also clump up and become useless.
Some major wheatpaste artists include Morley, Swoon, Shepard Fairey, ABOVE, Smear, and many others have made careers or political statements using this process. Mostly because it is cheap to make in large quantities as well as fast and easy to apply to walls. If you made your paste right and placed it in a hard to reach spot then that is all the better.