Nuclear Techniques Help Provide Zimbabwe Children with Healthy School Lunches

The schools had tried to initiate vegetable fields in the past, but had not succeeded due to the extremely harsh climate, arid conditions and poor soil fertility. In this part of Zimbabwe, it is difficult to have healthy gardens without irrigation. They also needed fertilizer, which is expensive and difficult to come by in the country. So, in accepting to help the schools with their fields, the team recognized the need to maximize resources and ensure their efficient use through small-scale drip irrigation.

The Joint Division had already been providing technical input to a regional technical cooperation project in 16 countries of Africa, focused on using nuclear techniques to establish protocols for the efficient use of smallscale irrigation systems. The national counterparts then showed local people how to determine the soil water situation and fertilizer needs, so that precious resources are not wasted.

When the Zimbabwean counterpart agreed to help the headmasters establish vegetable fields, he and his team carried out studies in their research station in Harare to determine when and how much water would be needed for the various crops. They used both the neutron probe and nitrogen-15 stable isotope tracers – tools that had been recommended by the regional project – to help the schools set up their fields in the most resource-efficient way.

A neutron probe is a sensor that measures how much water is beneath the soil surface and that works well for dry and cracking soil. The nitrogen-15 stable isotope technique traces the path of applied nitrogen fertilizers and determines if it is actually taken up by the plants’ roots and used efficiently. If fertilizer is not used correctly, it either remains in the soil and can be lost as a greenhouse gas that contributes to climate change, or it can be washed away, polluting water sources, not to mention that the overuse of fertilizer would mean that the funds used to purchase it were wasted.

In poor areas such as these, it is especially important to make the most efficient use of the purchased fertilizer. Once the decision was made as to the correct location for the vegetable fields, the school parents prepared the land themselves and carried out the planting. They planted kale, cabbage, onion and tomatoes and even sugar beans, which are considered important elements of a healthy diet. The counterpart continued to assist, providing advice on when and how much to irrigate, when and how much fertilizer to apply, and the best approaches to control pest.

Through this project, school parents have been able to harvest the produce to provide healthy lunches for their children at school and also for household consumption. And by selling what was left they can afford to pay for school fees. During the very first cropping cycle, the children had their school accounts credited – even before the produce was sold – because this new farming adventure was considered a surety for the funds being available. And surety that no child must learn on an empty stomach.