The Science of Greenhouse Gases

This article sheds light on how these practices differ in the contrasting climates of Europe, and South Africa to overcome the challenging inverse relationship between heating and plants’ need for CO2.  

The inverse relationship of heating and CO2

At the heart of greenhouse farming is photosynthesis – that magical process where plants turn light into life, taking in CO2 and releasing oxygen. But there's a twist to consider when it comes to heating, and the CO2 that is often released as a natural byproduct. 

Plants thrive on CO2 during daylight hours when photosynthesis occurs. However, heating is most prominent at night or in the cold winter months when photosynthesis is not as active. The result is that C02 is being produced at a time when it isn’t really needed, leaving the greenhouse rich in C02 that it can’t process naturally. 

This challenge is most common in the northern hemisphere where winters can get below freezing, and natural gas is abundant. But how can they use it to their advantage?

How greenhouse growers harness natural gas for heat and CO2

Greenhouse growers can capture this CO2, reintroducing it into the greenhouse, when needed, and boost plant growth through simple condensers. This is especially handy during the colder months when greenhouses in Europe can remain largely sealed off from the cold outside air, minimising heat loss and maximising CO2 utilisation.

With advanced systems that store heat and regulate CO2 dosing, European farmers can finely tune their greenhouse atmospheres, ensuring plants receive optimal conditions for growth even when external temperatures drop.

Heat and CO2 in the warmer climates of South Africa

The scenario shifts dramatically as we move to South Africa's warmer landscape. Here, the challenge is not about keeping the cold at bay but ventilating the excess heat to keep temperatures within an ideal range for plant growth – a practice that complicates CO2 supplementation. Without the C02-producing heating methods, some greenhouses find themselves low on C02. Even in scenarios where greenhouses require heating, it comes from burning coal and other fossil fuels and does not produce easily usable CO2 as a byproduct.

In South Africa, introducing CO2 into greenhouses often means purchasing it in gas form, an expensive and resource-intensive process for large scale farming operations. The need for frequent ventilation to cool the interiors means that much of this artificially introduced CO2 is quickly lost to the outside atmosphere.

Growing forward

Every greenhouse has its own climate, challenges, and needs. Balancing heating and CO2 is about knowing the rhythm of your greenhouse and learning to dance to it.

At Vegtech Netafim, we embrace these challenges as opportunities to innovate and provide our clients with sustainable, effective solutions for precision farming. Whether through advanced heating technologies, CO2 supplementation strategies, or solar-powered solutions, we are committed to helping farmers in Africa and beyond to minimise risks and maximise yields.

Interested in learning more about how we can tailor greenhouse solutions to your specific climate and needs?

Get in touch with us on +27 21 987 6980 or info@vegtech.co.za to see how we can help you grow more with less, wherever your greenhouse is rooted.