To create flower arrangements, people like to use floral foam for fresh cut flowers as a plugging compound. Since floral foam can not be reused well, it is disposed of in the trash after the flowers have faded.
There are different recommendations for the disposal of floral foam, from organic waste to residual waste. There are also various statements from manufacturers on the compostability of floral foam indicating that floral foam is “compostable”. However, there are different understandings of the term “compostable”. For example, there is the “biological decomposition” on the home compost pile and a complex industrial decomposition process.
I got really confused when diving into the topic. Therefore, I started an experiment, because I wanted to know if floral foam really rots on a home compost pile. I admit that I am rather skeptical about floral foam being compostable due to its ingredients. Floral foam is a synthetic resin foam and thus consists of plastic. According to many sources, such as the German Federal Environment Agency, plastic can not be completely decomposed and degraded. In the end, microplastic remains. See also: Floral Foam FAQ | Sustainability, disposal, microplastics,..
Experiment setup:
As a test object I used a faded rose arrangement of my own (see DIY | Romantic Table Decoration with Red Roses, Baby’s Breath and Chain of Hearts). I placed the faded arrangement in a bowl with other garden rubbish. The bowl was placed on my balcony and exposed to weather conditions such as wind, sun and rain. I took a picture at irregular intervals and recorded the changes with the camera.
Pictures from the experiment:
Day 1 |Beginning of the experiment: This is what the floral foam looked like when I put it outside with other garden rubbish:
Day 2 | After a day in the open air:
Day 5 | There are no visible changes yet:
Day 8 | The green floral foam begins to change color:
Day 47 | After 47 past days, the color change is clearly visible:
Day 59 | After 59 days, the floral foam on the “compost bowl” looks like this:
Day 92 | After 92 days, you can see clear discoloration on the floral foam but no visible decomposition yet: