A concrete solution: Examining Olla materials for sustainable farming

As the climate changes, water scarcity is becoming an alarming issue. The social and economical importance of water conservation via irrigation is becoming increasingly necessary. While there is abundant information on large scale irrigation systems, research is lacking on small scale systems. Additionally, existing irrigation practices are cost prohibitive for small scale farmers. One under-researched irrigation method is the use of ollas. Typically made from terracotta, ollas are placed underground and filled with water. Over time this water diffuses through the clay and slowly irrigates the surrounding soil with little water loss via evaporation. I evaluated alternative olla materials (concrete only and concrete with bamboo) for their effectiveness by irrigating baby leaf lettuce in a controlled setting. Concrete is both readily available and cost effective, while Bamboo is a fast-growing aggregate material with a small carbon footprint. I assessed the effectiveness of these materials through moisture readings, water diffusion rates, and germination rates. While terracotta olla’s had the fastest water diffusion rates, they were not statistically different from concrete with a bamboo aggregate ollas. There was no significant difference between the three tested materials during germination. However, after germination plant growth in the concrete without bamboo treatment was delayed. Our data suggest that ollas made of concrete with bamboo are as effective as traditional terracotta ollas and therefore may be an alternative cost effective and scalable irrigation method for small and independent farms in a changing climate. Poster submission was sponsored by Dr. Jessie Clasen, (Science and Technology Department) for course SRES 2100 and was presented at the New Westminster campus on April 11, 2024, for Student Research Days 2024.