Should the Time of year Impact your Produce Buying Decisions?

fresh produce in storefront


Have you ever wondered how to reduce the carbon footprint of your diet? Seasonality of produce is a good place to start.  

Introduction: Food production is responsible for a quarter of the worlds greenhouse gas emissions. There are various ways that the food system impacts the environment and many ways to reduce your personal impact, including what you eat and when. 
Greenhouse gasses are those which absorb infrared radiation from the sun. This heat is then trapped in the atmosphere, which increases the temperature and ultimately leads to climate change. Two of the most prevalent greenhouse gasses are methane, largely from agricultural practices, and carbon dioxide, which results from burning fossil fuels and deforestation. The impact on the environment caused by greenhouse gases is commonly referred to as a carbon footprint. 
There are many different aspects of food production that impact the environment. This includes, but isn’t limited to, land usage, transportation, animal feed, processing, retail, and packaging. Considering this fact, different food types impact the environment in different ways. It is important to understand this when making decisions about purchasing groceries.  
Many people think that buying local will reduce their carbon footprint. Though this is true, the extent depends on the product. Choosing local fresh produce reduces the carbon footprint of the product much more than choosing local animal products. Beef has one of the largest carbon footprints of any food, but only 0.45% is caused by transportation. Whereas with avocados, 10% of the carbon footprint is attributed to transportation. Choosing a local avocado would reduce the environmental impact by ten percent, versus choosing the local beef product would be less than half of a percent reduction. This comparison serves to show that there is not a “one size fits all” solution to sustainability in grocery shopping, but when it comes to produce, focusing on local seasonality is an easy choice with a big impact.  
Buying local produce eliminates the green house gasses given off by vehicles or planes. Another important factor to consider is whether this local produce is in season. Being in season simply means that the product grows naturally outdoors in that climate at that time of year. Seasonality of produce can be global or local. Global seasonality means that the item is in season where it is being grown. Local seasonality is when produce is both grown and consumed in the same region, in season. In short, the difference between global and local seasonality lies in where the consumer is located. 
Local seasonality has the smallest carbon footprint when it comes to produce; for example, buying locally grown squash in the fall. When you purchase produce out of season, it usually has to travel a long distance, which increases the carbon footprint. There are other ways which produce can be preserved or grown in a controlled environment, but these options also have a greater carbon footprint. While we are used to seeing blackberries year round at the grocery store, it is likely that a large amount of energy was used to provide the product if it is not a summer month. For these reasons, if you want to reduce the environmental impact of your diet, it’s important to be aware of when produce is in season. 
The chart provided shows Washington’s produce by season. Use this when possible to reduce the carbon footprint of your diet by choosing local in season produce. Remember that the seemingly small changes all add up to have the biggest impact on reducing carbon footprints. In addition to helping the environment, choosing regional food also gives back to the local economy, which directly benefits the farmers. Additionally, produce is of the highest nutritional value when consumed quickly after being harvested. Buying products in season has a positive impact on the planet, local community, as well as personal health.  
Our produce purchasing habits can have a big impact on the food system’s carbon footprint. There is no perfect solution to eliminating the environmental impact of your diet, but intentionality and small changes help. Being informed is the first step in the right direction, so you’re off to a good start. 

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