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International Journal of Horticultural Science

Vol. 32 (2026)
Articles

Enhancing African leafy vegetable productivity and nutrient levels through manure and fertilizer in Kitui County, Kenya

Published:
2026-03-09
DOI Linkhttps://doi.org/10.31421/ijhs/32/2026/15993
Authors
Alice Theuri,
Reuben Muasya,
Boniface Mwami,
Bonface Manono,
Benjamin Muli,
Regina Kamuhu,
Simon Nguluu,
Albert Luvanda,
John Wambua
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Keywords
African leafy vegetables hidden hunger nutrients nutritional deficiency manure application
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Copyright (c) 2026 International Journal of Horticultural Science

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This work is licensed under a Creative Commons Attribution 4.0 International License.

This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

How To Cite
Selected Style: APA
Theuri, A., Muasya, R., Mwami, B., Manono, B., Muli, B., Kamuhu, R., Nguluu, S., Luvanda, A., & Wambua, J. (2026). Enhancing African leafy vegetable productivity and nutrient levels through manure and fertilizer in Kitui County, Kenya. International Journal of Horticultural Science, 32(1), 52-60. https://doi.org/10.31421/ijhs/32/2026/15993
Abstract

African Leafy Vegetables (ALVs) are crucial components of diet globally due to their significant nutritional value. We conducted a field experiment in October 2022 to assess the effect of fertilizer application rates on the growth and nutritive value of four ALVs (Solanum nigrum, Cleome gynandra, Amaranthus hybridus, and Vigna unguiculata) at South Eastern Kenya University (SEKU) Teaching and Research Farm. We collected data through a randomized complete block experimental design that comprised four treatments: manure alone (M), fertilizer alone (F), manure + fertilizer (M+F), and a control (C). Once the planted vegetable seeds had been established, we counted their leaves on a weekly basis and averaged after a month. At the end of the experiment, the ALVs leaves were harvested. They were analyzed for retinol, a precursor of vitamin A, iron, calcium and zinc. It was found that manure and fertilizer treatments significantly increased the number of ALVs leaves. Results also showed that the Solanum nigrum had the highest number of leaves at 118.5% in M+F treatment as compared to the control. Across all vegetables, a combined treatment (M+F) significantly affected the retinol mean (P=0.0063) while crop type and the interaction between crop type and the treatment had no statistically meaningful impact on any nutrient. This suggests that fertilization effects on retinol are independent of crop type. These results highlight the importance of soil fertilization in influencing vitamin A levels in ALVs.

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