By Francis Ndungu

A 25-year-old student from Nyeri’s Tetu region, Martin Wanjau, returned to school and paid his own fees by building vertical cone kitchen gardens on his parents’ 50-by-100 metre plot. He now earns more than Sh10,000 a week from vegetables, with earlier earnings of Sh6,000 a week enabling him to clear his secondary school fees and finish Form Four in 2024.

“I went back to school and continued to pay my fees up to the latter and finished my secondary education in 2024. After there I enrolled into a nearby college to do an engineering course facilitated by the kitchen garden still,” he said.

Martin now manages 18 cone gardens, each holding 100 to 120 plants, and sells vegetables including spinach, kales, black night shade, spider plants, and pigweed greens. He also makes and sells Langstroth beehives at Sh6,000 each and constructs kitchen gardens for other farmers at less than Sh2,000.

“I was able to raise Sh10,000 in a week which enabled me to pay for my school fees on each semester without failing,” he said.

“After I joined Form One, two years later I dropped out from school due to school fees challenge,” he said.

His hopes revived when his mentor, Melvin, introduced him to kitchen gardening. “With kitchen garden I created my own job opportunity which enabled me to pay my fees,” said Martin.

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Martin fenced his parents’ plot and began with two cone gardens of spinach and kales, each with about 100 plants.

“Spinach and kales are rare in my region since no river nearby to support the growth of horticultural crops, therefore they were much expensive,” he said.

He explained how he built up the cones: “One vertical cone garden was filled with less than 12 wheelbarrows mixture of soils and manure. Out of the 12 wheelbarrows I used 6 to be manure which indeed boosted my production.”

He made six cones, each smaller than the one below: “The first cone is made up of 14 feet length joined together on a circular manner, the second one 12 feet, third 10 feet, fourth 8 feet, then 6 feet and 4 feet, forming a difference of two feet from one cone to the next.”

After four weeks, his spinach and kales were ready. “I realized that they were too much for my family since they had too many and broad leaves which was triggered by manure I incorporated during the erecting of the kitchen garden,” he said.

Martin began selling from his gate.

“I wrote a small notification outside our gate notifying people passing by on the road that spinach and sukuma wiki were available in my compound. Sometimes in the evening I plucked some of them and sold them outside my gate to willing customers who passed on the road. I sold them at bunch of 20, 30, 40, 50 each stem at Sh2. I was very impressed on the first day when I sold the vegetables worth Sh250 in a duration of less than 30 minutes,” he said.

Customer interest grew quickly. “Customers were very surprised to see the kitchen garden in my compound and asked so many questions like ‘how is it made?’ ‘Where did you get water to grow all these vegetables?’ With that kind of questions, they invited me to their homes where I aided them in making vertical cone kitchen gardens,” he said.

To meet demand, Martin increased his cones to eight and then to 18, adding other vegetables to cater for different customer needs. “Some demanded black night shade, others spider plants. That helped me earn more than Sh6,000 per week which became enough to take me back to school,” he said.

Along the way, he had to work out how to get enough water..

“There is no river in our area, thus it is difficult to do horticulture. With that challenge I came up with an idea of water harvesting where I bought 5 tanks and erected gutters around our house for the purpose of harvesting water in large quantities during rainfall season. With five tanks each accommodating 20,000 litres, my plants survived for more than 3 months even when rain failed,” he said.

Martin raised his own seedlings. “I selected a site on the corner of our plot where the soil was well drained and the area was free from water logging. I dug the nursery bed, removed all the roots, debris and large clods of soil, and raised the nursery bed 1 metre width and 3 metres. I fine-tilled the nursery and made shallow drills of 5cm spacing and sowed the seeds, covered them shallowly with fine soil and later covered them with dry grass and watered them,” he said.

He transplanted after four weeks when the seedlings were pencil thick with 3–4 leaves. “I later transplanted my vegetables and increased my cone gardens to 8 to increase my daily earning,” he said.

“Pests were the major challenge especially mites, aphids, whiteflies and birds. Birds however were the biggest challenge as they were difficult to control but as time went by, I got rid of them,” he said.

He controlled birds and whiteflies with a net. “Initially birds caused a lot of losses as they ate all the leaves on my garden but later, I erected a net around and over my garden and constructed only entrance door and kept them off my garden. However, the net also helped in eliminating whiteflies on the garden as it had tiny holes where the flies could not fit,” he said.

He also used companion planting: “I planted onion splits around the vertical garden. Onions produced an awful smell which the aphids did not like, making them disappear. I also planted hot peppers around the garden which worked effectively by suppressing caterpillars and aphids.”

For spider mites, Martin improvised: “I normalised in doing showering during the day when the temperatures were very high inside the kitchen garden. Showering broke down the lifecycle of the mites. Showering was also useful to my plants as it helped in regulation of heat during high temperatures,” he said.

He also battled snails. “I read an article on FarmBizAfrica where snails were controlled on strawberries using crushed eggshells plus common salt and decided to give a trial on my kitchen garden and it fortunately worked perfectly,” he said.

Martin said indigenous vegetables were always in demand. He sold spinach at Sh40 per kilo, normal kales, curled kales, night shade, spider plants and pigweed greens at Sh50 per kilo.

“I planted kales on 4 vertical cone gardens, 3 cones on curled kales, 3 on night shade, 5 cones on pigweed and 3 on spider plants. Each cone garden accommodated 100–120 plants at a spacing of 15cm from one plant to another which grew so vigorously in presence of manure,” he said.

Martin has now also expanded into making beehives after noticing a local gap.

“I saw farmers travelling all the way to Meru to buy beehives. I started with two beehives which were bought instantly. The demand increased as time went by and I started selling to farmers at Sh6,000 per Langstroth hive. I later became a topic in my village after being able to sell beehives across our region,” he said.

“I normally sell the kitchen garden materials to my clients and also visit their homes to help prepare it if need be. Out of the same I also sell the beehives at Sh6,000 per hive,” he said.

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