Imagine growing food without soil, using only coconut waste, water and carefully measured nutrients. A group of innovative students at Kiambu National Polytechnic (KINAP) is making this a reality, offering a promising solution to food security challenges.
Traditional farming faces numerous challenges, including soil degradation, pests, diseases, and high water consumption. Poor soil quality often leads to lower yields, while soil-borne diseases force farmers to rely on chemical treatments that can negatively impact both health and the environment.
Recognizing these issues, Mary Njoki and seven collegemates sought a cleaner, more sustainable alternative.
“Our solution is a soil-less farming system that replaces soil with coconut refuse, also known as cocopeat, and hydroponic nutrients to grow fresh, healthy produce,” says Njoki.
The cocopeat acts as a growing medium. Unlike soil, it is lightweight, retains moisture effectively and promotes proper aeration, ensuring that plants receive the nutrients they need without the risk of soil compaction.
The nutrient solution, made by mixing Hydroponics A and B in equal measures with water, provides essential minerals for plant growth.
“The setup consists of water pipes fitted with elbows at the ends to prevent spillage. Circular spaces are cut into the pipes to hold tumblers, which have slits on the sides to allow the solution to seep through.
These cups contain coconut refuse and the growing plants’’, said Njoki.
The pipes are placed on a wooden structure that maximizes space that the same area of land occupied by the structure would accommodate significantly fewer plants if traditional methods were used
One of the most appealing aspects of the project is its cost-effectiveness. A kilogram of cocopeat costs Sh. 120, hydroponic nutrients cost Sh. 100 per packet, and tumblers cost Sh. 120 each, making the project affordable for small-scale farmers and urban households.
“Another big advantage is that it’s versatile. You can set it up anywhere—on a balcony, a rooftop, or even indoors with proper lighting. You don’t need to be an expert to try this at home. All you need are a few basic materials and you can start growing your own vegetables and herbs. It’s a great way to ensure you have fresh, healthy food at your fingertips,” says Njoki.
The idea was born out of a desire to address food security and provide solutions for areas with poor soil or limited planting space.
“We wanted to create a farming method that saves space and time while eliminating concerns about soil type and acidity. Producing clean, chemical-free food is an added benefit,” Njoki explains.
Dr. Samuel Kariuki, an agricultural expert and lecturer at KINAP, lauds the students’ innovation.
“Hydroponics is the future of sustainable farming. With climate change and urbanization limiting available land for agriculture, soilless farming techniques like this can be a game-changer, especially for food production in cities,’’ says Kariuki.
The KINAP students are already seeing positive results. Their leafy greens and herbs grow faster than traditional crops and they are exploring ways to scale up production. They hope to introduce the technique to local farmers and schools to encourage widespread adoption.
“We are currently testing different plant varieties to determine the best nutrient combinations for optimal growth. Our goal is to expand this project and create awareness about modern farming techniques,” Njoki adds.
Their project is more than an academic exercise. It is a blueprint for the future of farming. By turning coconut refuse into a valuable resource and eliminating the need for soil, these students are addressing food security, promoting sustainability and empowering individuals to grow their own food—no matter where they live.
The team plans to conduct workshops and training sessions to educate the public on hydroponic farming. They invite individuals, schools and community groups to learn more and participate in the movement towards sustainable agriculture.
By Joyrita Nyambura
