Plastic and Kitchen Gardening
The Plastic Problem
Although the first plastic was produced in 1907 it wasn’t until the 1950’s that plastic production became industrialised. In 2015 it was estimated that it was estimated there were 381 million tonnes of plastic produced globally. In 2018, plastic pollution became a hot topic – the so called ‘David Attenborough effect’
How does plastic pollution fit with the ethos of Kitchen Gardening? What is the impact of plastic in the garden? Are there alternatives? As kitchen gardener’s what can we do to help?
There is no doubt that plastic is having a negative impact on our oceans and wildlife. However, the impact of plastic on our planet is a complex issue. Non-biodegrable waste will ultimately end up in our ecosystems and our food chains. The carbon cost of production and transportation of all items needs careful consideration and it is important to bear in mind that plastic as a material has many benefits: it is cheap, lightweight and durable.
Can we just not recycle plastic or make biodegrable alternatives?
Currently, 90.5% of plastic goes un-recycled worldwide, a figure calculated by industrial ecologist Roland Geyer, which made statistic of the year for 2018. Even if we could create the infastructure to up the recycling rate it may not make the impact you could imagine. Research at Southampton University looked at the net carbon emissions for recycling different products compared to producing from raw materials. There was a net carbon saving to recycling plastic, but it isn’t that great – recycling Alumininum cans saves 8 x more the carbon than recycling plastics! (Turner, Williams, & Kemp, 2015). Over time there is hope that recyling will become more efficient, but currently recycling plastic alone isn’t an answer!
Bioplastics suitable for food packaging are currently under development. In theory, these are carbon neutral as they are produced from plants which capture carbon as they grow. When they are composted the carbon is released back into the atmosphere. However, recent research suggests that when emissions from manufacturing and transportation are taken into account the saving on carbon emissions is under 30% (Dormer, Finn, Ward, et al, 2013).
Buy what you need and reduce waste in general
The best way to reduce plastic waste (and carbon emissions in general) is to simply reduce the amount of stuff you buy! If items are not being produced, packaged and transported they don’t end up polluting ecosystems or contributing to global warming. If could all adapt our lifestyles to live a little less commercially we would move towards a much more sustainable future.
Is plastic that bad in the garden?
You may wish to consider the local effect of plastic in your garden or allotment. Plastic items have become a mainstay of gardening – plastic pots, containers, weed supressant matting, tools – you name it most are made of plastic. However, plastic is a very useful material in a garden and it is pretty difficult to elimate it completely. Reducing single-use plastic and items that are made from plastic that do not stand up to the weather well and break down easily. Buy cheap, buy twice! Items that degrade in sunlight and break down easily are blown by wind into hedges or layered into your ground over time. Plastic netting is a hazard for small animals and birds, especially when discarded or broken down.
Here are my top 10 tips for reducing plastic waste/re-using plastic in your kitchen garden
- Buy sturdy hard-duty plant trays or pots that will last for a years. We like Oaklands 30L pots for growing potatoes.
- If you wish to use plastic membrane ensure it is heavy duty. Choose one that is 100gsm. If used well this will last 5+ seasons. Consider using thick carboard layers or a compost mulch as an alternative.
- Avoid using blue visqueen/viscuene as a weed supressant at all costs – it shatters into a million tiny pieces as it becomes unstable in the sun.
- Try using recycled containers to start seeds e.g. yoghurt pots or biodegradable options such as toilet roll inners or paper pots that can be transplanted straight into the ground.
- If using cardboard as part of your composting, try to remove all the cellotape packaging before adding it to the heap.
- Avoid using cheap/thin netting that will rip easily in windy weather. Environmesh is strong stuff and will easily last up to 10 years. Much better than replacing netting or fleece annually.
- Buy items in bulk or locally where you can. At our ground we have an allotment shop where you can buy supplies such as canes. These are bought in bulk reducing transportation emissions of ordering your own.
- Consider building projects from recycled materials where possible. For example, a coldframe from recycled wood and glass will last much longer than a cheap plastic bought one for the fraction of the price. We are currently building a summerhouse using (mainly) recycled materials including double glazed doors and frames that would have ended up at the tip and the timber framework of an existing summerhouse.
- Wash your veg picked at the plot and then use material/re-usuable bags to transport your products home. Better still get a 4-wheeled garden trolley if you plot is close to home. We predominantly use ours without any carrier bags.
- Use natural twine that is biodegradable.
Finally: Plan your garden to be as productive as possible – grow more, buy less! By growing your own food, you are having a big impact on both carbon emissions and plastic pollution. You are doing a great job!
References
Dormer, A., Finn, D. P.,Ward, P., et al. (2013). Carbon footprint analysis in plastics manufacturing. Journal of Cleaner Production. In press.DOI: 10.1016/j.jclepro.2013.01.014
Jambeck, J. R., Geyer, R., Wilcox, C., Siegler, T. R., Perryman, M., Andrady, A., … & Law, K. L. (2015). Plastic waste inputs from land into the ocean. Science, 347(6223), 768-771. Available at: http://science.sciencemag.org/content/347/6223/768.
Turner, D., Williams, I., & Kemp, S. (2015). Greenhouse gas emission factors for recycling of source-segregated waste materials. Resources, Conservation And Recycling, 105, 186-197. doi: 10.1016/j.resconrec.2015.10.026