the many biodiversity and climate benefits of strawberries – A greener life, a greener world

By Anders Lorenzen

In this series, we look at individual crops and how they fare in a warming world. 

After we examined the rye grain in the first article, in our second instalment, we stay firmly rooted on the ground as we look at one of the world’s most treasured fruits, strawberries. 

A brief history of strawberries

Strawberries, a tasty summer fruit dating back to Roman times, properly took off in the 18th Century as it became a cultivated crop. 

During 2023, over 10 billion tonnes of strawberries were consumed.

From a wild berry to 600 varieties

The strawberry plant is related to the rose family, which includes other fruit and berry species such as apples, pears, plums, raspberries and ornamental plants such as roses. 

Over 20 species and 600 variants of strawberries consumed worldwide today stem from around six original wild species. Additionally, various hybrids and subspecies have emerged from these.

Strawberries and biodiversity

The strawberry plant can play various positive biodiversity roles.

As with most things, the devil is in the details and is dependent on how it is cultivated.

Soil health

Strawberries cultivated organically have been shown to positively influence soil microbial diversity.

Strawberries cultivated organically have been shown to positively influence soil microbial diversity.

When organic fertilisers such as pig manure and calcium cyanamide are applied,, they reduced soil-borne diseases and enrich the soil with various beneficial microbial communities. They play an essential role in the cycling of nutrients, as well as the suppression of diseases, and so enhance the soil’s overall health.

Improving fertility

When biochar has been incorporated into strawberry farming practices, it has significantly improved soil quality. 

It increases the soil pH value through organic carbon content, cation exchange capacity, and microbial biomass carbon. These enhancements contribute to better soil structure, fertility and water retention, vital for sustainable strawberry production.

Organic matter and nutrients

When organic rather than conventional strawberry farming practices are applied, it has been associated with higher levels of soil organic matter, and carbon and nitrogen content. This further improves soil quality, enhances water infiltration, and supports a more robust microbial ecosystem.

Climate and carbon

Due to their large root systems, strawberry plants have significant carbon capture and storage properties.

Using biochar in strawberry cultivation yields benefits beyond soil health. Biochar contributes to carbon sequestration by creating a stable carbon pool in the soil, effectively acting as a carbon sink and reducing atmospheric CO₂ levels. 

Additionally, strawberry plants form symbiotic relationships with mycorrhizal fungi, which are instrumental in soil carbon storage. These fungi can hold a significant portion of the total carbon stored in soil, aiding in long-term carbon sequestration and enhancing soil fertility.

Strawberry carbon footprint

It goes without saying that growing your own strawberries results in the lowest carbon footprint. But this, of course, is not always possible, as you may not be able to grow enough for your consumption, and they might not be ready when you need them.

But how you purchase strawberries can significantly influence the carbon footprint.

While locally grown products have many benefits, in terms of the carbon cost, this is not always the case. In this carbon analysis, we have used the UK as an example. The data shows that importing strawberries from Spain to the UK has a lower carbon footprint than growing them in the UK, even when grown in season without any heating needs. 

There are many factors at wor,k such as larger farms, longer growing season, better and more efficient packaging methods, higher penetration of renewables in the growing area and low-carbon trucking transport. 

UK seasonal grown strawberries without artificial heating

Using the UK as an example, purchasing in-season, field-grown strawberries with the peak season typically being from May to July has a carbon footprint of approximately 0.17 kg CO₂e per 200g punnet. This low carbon footprint is made possible by no artificial heating needs.

UK-grown strawberries with artificial heating

However, the carbon footprint significantly increases when grown out of season in heated greenhouses to approximately 0.80 kg CO₂e per 200g punnet.

Imported from Spain by road

The carbon footprint significantly decreases when they are imported from Spain, depending on which of the two different metrics is used:

Road transport produces a carbon footprint of approximately 0.12 kg CO₂e per 200g punnet.

Imported from Spain by air

However, if it is transported via air, the carbon footprint is approximately 0.38 kg CO₂e per 200g punnet.

How to interpret the carbon data

To understand how to relate to these carbon footprints, it may help to compare them: 

• 0.12 kg CO₂e – equivalent to driving 0.5 km in a small petrol car.
• 0.17 kg CO₂e – equivalent to using a LED light bulb for 24 hours.
• 0.38 kg CO₂e – equivalent to a 2.5 km car journey or charging a smartphone 30,000 times.
• 0.80 kg CO₂e – equivalent to a 5 km car journey or boiling your kettle 10 times.

Anders Lorenzen is the founding Editor of A greener life, a greener world.