Food Security Sustainability Climate Change Agriculture
Science Film Festival Films How Will We All Eat Enough Tomorrow? Learning Goals This experiment aims to compare harvest quality and yields from three crops grown together in a polyculture with each crop grown separately in a monoculture. Our main question is: Is there a difference in yield of beans, spinach and radish when grown as a polyculture compared to when grown as monocultures? a) Total yield (grams per square meter) b) Yields of each crop
We also have the opportunity to look at changes in three soil nutrients – nitrogen (N), potassium (P) and phosphorous as potash (K) – and soil acidity-alkalinity (pH).
Explanation of Scientific Principles Food production and consumption have a big impact on society, soils, ecosystems, biodi- versity and on climate change. Polycultures – growing several crops together at the same time – have been shown to have benefits in terms of crop yield, resilience to pests and disease, and enhancing wider biodiversity. Preparation Explanation of Connection to the Film Large-scale monoculture farming is now considered environmentally harmful and unsus- 1 There are four plots tainable. We need to understand alternative ways of farming, especially polyculture. In the needed for the experi- next 50-60 years, the era of fertilizer-based farming might come to an end because we are ment. They should be fast exhausting naturally-found minerals like potassium used in fertilizers today. There is adjacent growing areas an urgent need to find clean and sustainable ways of growing food for all citizens of the that are separated planet earth, and learn how to preserve biodiversity by truly understanding how nature from each other by really works. at least 50 cm. The plots should be free of weeds, and all prepared in the same way according to your usual methods (e.g. dug over, composted for no-dig).
You can refer to the detailed instructions and print out a record- ing sheet that can be found at Grow Obser- vatory website: knowledge.growobser- vatory.org/article-cat- egories/polycultures- v-monocultures/ Polycultures vs. Monocultures
Materials 1 • Seeds/seedlings for: 18 seeds – Climbing green beans “cobra” variety – Phaseolus vulgaris “cobra” 72 seeds – Spinach “matador” variety – Spinacia oleacea “matador” A step by step instruction for 160 seeds – Radish “cherry belle” variety – Raphanus sativus “cherry belle” planting and layout can be found here: It is also worth keeping a few extra seeds for spares in case of germination failure. If these varieties are not available in your country, please choose closely related varieties of the knowledge.growobservatory. same species org/knowledge-base/how-to- set-up-the-experiment/ • 18 garden canes to support the beans (at least 1.8 meters high). • Scales to weigh harvests. 2 • GROW recording sheets and pencil/pen for observations on the plot (to upload when home). Many aspects of growing • Gardening tools for preparing the soil, planting seeds, cutting your harvest and watering could affect your results, so if you need to. it’s useful to record notes. • Find a good growing site This can be used to help understand any odd results To grow well your crops will need a site that is not water-logged and has good levels of you get later. light. If you don’t already have a site where you grow food, you can use two simple tests to identify a suitable site – 1) Testing soil with the squeeze and sniff test, 2) Assessing light and shade. 3
You can fill these results in on your recording sheets or a notebook. For more informa- tion and resources, please visit: Grow Observatory.
100 cm 50 cm 30 cm 100 cm 40 cm 2 1
2 Spinach alone
3 100 cm
4 3 60 cm
Polyculture Radishes alone Beans alone
Beans Shade underBeans/ Spinach Radish 1 2 1st to Tripod of 9 per plot space needed 36 per plot 80 per plot 3 4 4th sow canes
medium.com/grow-observatory-blog/polycultures-v-monocultures-the-great-grow-experiment-2018-5fac8a6a3879
knowledge.growobservatory.org/article-categories/polycultures-v-monocultures/
www.otffeo.on.ca/wp-content/uploads/sites/2/2014/07/Grade-6-Lessons-Biodiversity.pdf