Imagine realising that instead of waiting three hundred and sixty-four days for Santa’s presents to arrive, you could just clone him and have them appear every day. Now imagine the same with food.
That’s right – you don’t have to.
Technology can recreate the varying conditions for mass food production just about anywhere, so the people demanding asparagus can get their asparagus the moment they hit Waitrose.
Just because produce is available to buy in the supermarket doesn’t mean it’s in season. Do you remember when craving a Crème Egg meant going without that gooey centre until Easter? Now we can have them delivered to our door in time for Christmas.
We grow ‘natural’ produce even when it’s not meant to be grown, or we buy it from another country where they have the right production conditions. Are the energy costs associated with these foods bad for the environment?
Unfortunately, there’s no straightforward answer. But it’s useful to know where your food comes from and the energy involved. Here’s everything you need to know about food seasonality.
- What is seasonality?
- Where does our food come from?
- Issues impacting food sustainability
- Which foods are the most sustainable?
- When are foods in season in the UK?
- Seasonality calendar
- So is eating seasonally better for the environment?
What is seasonality?
The Defra definition (or Defranition, if you will) of ‘seasonal’ is simply, ‘produced in season’, which refers to locally and globally grown foods. ‘Local seasonality’ is defined as ‘food that is outdoor grown or produced during the natural growing period for the country or region where it is produced’.
When asked about seasonality, many participants in the above Defra study believed it meant locally grown fresh fruits and vegetables with a lower carbon footprint from less travel.
This is only partly true. Seasonality also affects meat, fish, and crops, and freight energy is often far from the biggest environmental concern.
Where does our food come from?
Approximately half of our food is grown in the UK. Of our fruit and vegetables, almost three-quarters are imported from the EU, but the number of non-EU imports has risen alongside exotic food trends. Fruit is by far the most imported, as few can be naturally grown here.
We rely heavily on other countries for our food because of the conditions required to grow specific produce. It is technically possible to grow more of our food locally, however several studies suggest that if the UK were to become self-sufficient, our emissions would be greater.
Issues impacting food sustainability
The biggest factors in food carbon footprint are:
- On-farm production (water and heat energy, land occupation, resource depletion)
- Packaging and refrigeration (especially of fragile produce)
- Transportation (fuel and acidification)
Food production processes are the absolute worst culprit, accounting for a quarter of the entire world’s greenhouse gas emissions, whereas transportation accounts for approximately 0.59% of the UK’s Greenhouse Gas (GHG) contributions.
The production depends on the type of food grown and its required growing conditions, which is such an unpredictable variable that there’s no one-size-fits-all solution. Energy use is impacted by resource efficiency, agricultural practices, amount of heat, soil type, and the availability of water and sunlight, so the same produce from different regions can vary in environmental impact.
If a food from overseas uses less energy in production, or yields more for the amount of energy used, the imported food may be better than a local food using more energy in production. If one greenhouse in Europe is growing potatoes at a faster rate than several British potato fields, the reduced land, water, and pesticide usage may make the import more sustainably viable.
So eating globally-produced food isn’t necessarily a bad thing – it depends on the production.
Refrigeration, packing, and transportation can also contribute significantly, especially when the food requires lower temperature storage than other produce, like exotic fruit. One estimate suggests that refrigeration energy accounts for about 27% of total energy use in the food manufacturing industry, with refrigerated transport adding a further 15% to emissions.
Out-of-season production requires artificial energy, either directly or indirectly, which depletes our natural resources and increases greenhouse gas emissions. Importing foods when they’re in-season elsewhere can be better if they are grown naturally, but the resources used in the cultivating country also need to be considered.
Which foods are the most sustainable?
There is no definitive answer to this. Whether a food is sustainable or not depends on the use of energy and available resources during production.
As stated in the above section, the local environmental conditions and resources required to grow produce varies by region, so the energy usage also varies. This means we can’t say that any one particular fruit or veg is better or worse for the environment. You can, however, make educated guesses.
Root vegetables, brassicas (e.g. cabbage and broccoli), apples, pears, and any other indigenous foods are likely to have a lower impact. The least greenhouse gas-intensive produce is field-grown seasonally in the UK without artificial heating or protection.
However, the cultivation of locally sourced, field-grown fruit and vegetables still isn’t ideal. Some energy consumption occurs when coercing seeds into seedlings in heated greenhouses, as well as from farm machinery and the manufacturing of vital fertilisers and pesticides. Despite this, these fruit and vegetables are likely to have lower carbon footprints.
Certain imports are also surprisingly low impact. Robust produce from overseas which were grown without artificial heating and were transported by sea or road are relatively low in GHG intensity.
The humble banana is considered low impact, as they are usually sea-freighted without refrigeration, so you won’t have to stop drinking smoothies for the good of the earth!
Air freighted food is by far the worst offender for transportation emissions, of which fruit and vegetables are the largest group.
The volume of air freighted produce increases alongside food trends for exotic fruit and veg, like the avocado phenomenon of ’15 that took the hipsters by storm. This shows that our eating habits definitely do impact GHG emissions.
The foods most likely to be flown in are highly perishable items such as imported lettuce, pre-prepared salad bowls, and fruit. Not only does this use a significantly larger amount of energy in transportation, but also through full lifecycle refrigeration and higher likelihood of wastage.
Many fruits and vegetables like mangoes and asparagus are almost always flown in. Berries from America and peas and beans from Africa also fall into this category.
Mediterranean vegetables like tomatoes and courgettes can be grown in the UK, but usually need energy-intensive greenhouses to replicate their growing conditions. If imported, the biggest carbon footprint concerns for these items are transportation and refrigeration.
It is believed that fruit and vegetable consumption in the UK equates to around 2.5-3% of all carbon emissions in the UK. Other foodstuffs such as meat are much higher.
Beef products are by far the worst foods for greenhouse gas emissions, amounting to 60kg of CO2 equivalent for every 1kg product.
For comparison, chicken has 6kg for every 1kg.
So sorry to break it to you, but veggies and vegans kind of have been saving the world all along.
(You don’t have to go ham and be a full vegetarian to make a difference (excuse the pun). You can just cut down your meat consumption. I have at least one vegetarian meal a week, and they’re genuinely great).
When are foods in season in the UK?
Several types of fruit and vegetables are available for most, if not all of the year. You may already know some from holiday seasonality, such as pumpkins in late autumn, but it’s good to brush up on the more common produce.
Below is a seasonality calendar of when fruit and vegetables are grown in the UK:
UK Fruit and Veg Seasonality Calendar
Please note: this list depends on the variety of food. For example, the below resource shows apple varieties and when each is in season: https://britishapplesandpears.co.uk/production/the-british-season-apples/
If you’re not keen on my beautiful calendar, there’s the BBC Good Food interactive table that can be filtered by month or by food type, and the VegSoc list of produce by month, which was my original source (I won’t take offence, they’re both great resources!).
So is eating seasonally better for the environment?
Eating seasonally would likely have a positive impact on the environment if enough people did it, however, as explained in this post, it’s not a straightforward solution. The biggest issue isn’t so much the where and when of food production as it is the how.
Fruit and veg grown out of season are definitely more energy-intensive. For instance, out-of-season strawberries and tomatoes have likely been grown in heated greenhouses, but during their growing season may not need heating at all.
Basically, eating seasonal produce will reduce your emissions, but only slightly. Some foods are more energy-intensive than others, regardless of seasonality.
In-demand non-seasonal produce means more surplus and more waste, so the additional energy put into producing, transporting, and refrigerating the food is all for nothing, with the end product itself becoming a contributor to GHG. Seasonal eating can reduce this likelihood.
Remember though, just because a food product is from another country doesn’t necessarily mean it’s bad for the environment. If it’s been transported by sea or road and grown in natural conditions, then it’s probably okay. The difficulty is in knowing this for sure.
The best thing we can do is educate ourselves on where our food comes from and how it was produced before our weekly Tesco trip. Check the packaging for product origins, and ask yourself –
- Is the time of year right for this food?
- Is the food both highly perishable and from overseas?
- Am I likely to use all of this product before its use-by date?
- Are there other recipes I can make with the leftovers?
- Do I need to have a beef lasagne, or could I try turkey or pork mince instead?
If everyone followed these simple steps, we would reduce food carbon emissions considerably.
I hope you find this resource useful. Let me know in the comments what you’re doing to reduce your carbon foodprint!
Research source: https://www.fcrn.org.uk/sites/default/files/Fruitnveg_paper_2006.pdf