TOPIC 2: In diversity we trust

TOPIC 2: In diversity we trust

In this topic we will learn about the decreasing diversity of food plants and why it is important to take countermeasures.

Diversity in food and agricultural plants is under severe threat.

DID YOU KNOW?  In the world’s food production plant based food is made of only 30 species (out of app. 7.000 we know).

Within the last 100 years about 75 % of the worlds cultivated food plants got lost. Agriculture is becoming less and less diverse in terms of ecosystems, species and within-species genetic resources they comprise.


Loss of biodiversity in turn threatens the capacity of fields and meadows to sequester carbon and reduces the options to adapt to and mitigate climate change.

“Biodiversity is critical for safeguarding global food security, underpinning healthy and nutritious diets, improving rural livelihoods, and enhancing the resilience of people and communities. We need to use biodiversity in a sustainable way, so that we can better respond to rising climate change challenges and produce food in a way that doesn’t harm our environment,” said FAO’s Director-General José Graziano da Silva.

Today we cannot predict which plant species or varieties will one day be the ones best adapted to changing conditions. Diversity makes our gardens more resilient when hit by late frosts, heavy rains or longer dry periods.

They might affect certain plants but won’t do so with others. Also new pests and diseases are often bound to specific species or even varieties. To minimize the risk of a total loss of harvest planting a great variety of plants can act as an insurance. Heritage plants can be well adapted to different climates, even drought resistent but also more vulnerable to different pests and diseases. Locally bread varieties might be especially well adapted to the local conditions and therefore be a good choice.

Home gardens and community gardens can act as a refuge for agrobiodiversity, using a large variety of plant species and varieties and thereby conserving plant genetic resources. Seed propagation of locally adapted varieties can be an extra activity to contribute to climate change adaptation.

Diversity beyond vegtables

Biodiversity in our gardens does not only mean the vegetables in our beds or the fruit trees in our orchards but also many other species of plants, animals and micro-organisms that contribute to food growing, whether by creating and maintaining healthy soils, pollinating plants, purifying water or providing protection against extreme weather events. Especially in a changing climate our food plants are more and more stressed due to sun, heat, drought or frost as well as newly appearing pests and diseases. Therefore it is even more important to create an environment that attracts beneficial organisms. This can be planting flowers and herbs in our vegetable beds, bushes inbetween and creating diverse meadows or wild corners around. You can also use wild plants to enrich your diet. Many “weeds” that grow in our gardens are edible for humans and important for many other organisms. Apart from protecting our harvest by creating such habitats we can make an important contribution to fight the biodiversity crisis. (see also topic biodiversity)

Sources and further information

Arche Noah: wozu Vielfalt accessed in June 2023

Lehr- und Forschungsgebiet Beratung und Kommunikation Humboldt-Universität zu Berlin, Albrecht Daniel Thaer-Institut für Agrar- und  Gartenbauwissenschaften, Themenblatt Pflnzenschutz im Klimawandel: tb_5_pflanzenschutz-im-klimawandel_web.pdf , accessed in June 2023

University of Weihenstephan: Garten-Klima: Biodiversität: accessed in June 2023

FAO, The biodiversity that is crucial for our food and agriculture is disappearing by the day accessed in June 2023

FAO State of the World’s Biodiversity for Food and Agriculture report accessed in June 2023