CHAPTER ONE

INTRODUCTION

1.1 Background of the Study

Maize is one of the major cereal crops cultivated in Nigeria, and its demand is considerably higher than the quantity produced locally. According to a report by the News Agency of Nigeria published in 2025, the country's annual maize requirement was estimated at approximately 21 million metric tonnes, while production was reported to be about 10.5 million tonnes (AllAfrica, 2025). Addressing this production gap requires either expanding the area used for maize cultivation, improving productivity per hectare, or adopting both approaches. For small-scale farmers, who account for a large proportion of maize production, improving yield depends greatly on maintaining adequate soil fertility.

Soils in the northern savanna regions, where a significant proportion of Nigeria's maize is cultivated, are generally deficient in essential plant nutrients. Tofa et al. (2022) explained that Nigerian savanna soils contain low levels of nitrogen and phosphorus, which negatively affect maize productivity. Similarly, Kareem et al. (2017) observed that savanna soils are often poor in nutrients and that farmers depend on both organic and inorganic fertilisers to maintain crop production. In their study conducted in Zaria, within the northern Guinea savanna, Tofa et al. (2022) reported that applying phosphorus at 13 kg/ha increased nitrogen uptake by 51% and 57% at nitrogen application rates of 60 kg/ha and 120 kg/ha, respectively, compared with the treatment without nitrogen. This finding demonstrates that applying nutrients in combination can improve nutrient uptake more effectively than applying individual nutrients separately.

Mineral fertilisers are important for achieving relatively quick improvements in maize production. However, their increasing cost has made them difficult for many small-scale farmers to afford. A market survey published by BusinessDay reported that the average price of a 50 kg bag of NPK fertiliser increased from approximately ₦43,000 to ₦60,500 within one year, representing a rise of about 41% (Okojie-Okeiyi, 2025). Farmers interviewed by the News Agency of Nigeria also reported reducing maize cultivation because the cost of fertiliser had become too high compared with the market price of maize (AllAfrica, 2025). Consequently, farmers who cannot afford the recommended quantity of NPK fertiliser may reduce their application rates, stop using it altogether, or seek alternative sources of soil nutrients.

Organic materials provide one possible alternative to mineral fertilisers. A panel survey of maize farmers in north-western Nigeria found that animal manure was the most commonly adopted soil conservation practice. Its adoption rate was 76% in the 2016 farming season and 69% in 2017. The study also reported that farmers commonly combined two soil conservation practices, with animal manure and the retention of crop residues being the most frequently used combination (Oladimeji, 2020). Other factors influencing adoption included livestock ownership, access to credit and the use of inorganic fertilisers. These findings indicate that organic materials are already part of the soil management practices of many maize farmers in northern Nigeria. Their use may complement mineral fertilisers rather than serve only as a replacement for them.

Research conducted in different parts of Nigeria has shown that organic materials can improve maize growth and yield, particularly when combined with mineral fertilisers. Kareem et al. (2017) reported that applying poultry manure at 5 tonnes per hectare significantly improved the growth and yield characteristics of maize. Similarly, Onwubiko (2026) found that poultry manure applied at 10 tonnes per hectare produced the highest leaf number and leaf width among the local maize varieties examined in Nsukka. Compost, which farmers can prepare from crop residues, animal waste and other farm materials, has also been examined in comparison with mineral fertilisers. Okhumata and Idowu (2022) investigated the effects of compost–mineral fertiliser, NPK and urea on maize yield, including the appropriate timing for applying the compost–mineral fertiliser. Evidence of the benefits of combining organic and inorganic nutrients is also provided by Akinmutimi and Okoroji (2024), whose study on amaranth production in Umuahia found that combining poultry manure with NPK produced a higher yield than using NPK alone.

Zaria Local Government Area is located within the northern Guinea savanna zone of Kaduna State. It is one of the three local government areas in the state with adopted villages under the National Agricultural Extension and Research Liaison Services (NAERLS). The area has seven adopted villages and 1,225 registered farmers (Abubakar et al., 2022). The presence of agricultural research and extension institutions may provide maize farmers in the area with greater access to information and recommendations on fertiliser application and organic soil amendments. However, the actual practices of these farmers are not sufficiently documented. Some may apply compost alone, others may depend entirely on NPK, while some may combine both inputs or use neither. Farmers may also differ in the quantities applied and the stages of crop development at which they apply them. The available literature reviewed for this study does not adequately establish the growth and yield outcomes that farmers in Zaria report under these different application patterns.

A questionnaire-based survey provides a suitable approach for obtaining this information. Through a survey, the researcher can establish the proportion of farmers using each fertiliser pattern, the quantities of compost and NPK applied, their application periods, farmers' observations of maize growth and yield, and the challenges affecting their use of these inputs. Although a survey cannot independently establish the effects of compost and NPK because factors such as soil conditions, rainfall and farm management may also influence crop performance, it can provide useful information about farmers' experiences. The findings can also help determine whether farmers' reported experiences are consistent with results from previous field experiments and identify areas where differences exist.

1.2 Statement of the Problem

Maize farmers in Zaria require adequate soil nutrients to achieve satisfactory yields because the soils in the area are naturally deficient in important nutrients, particularly nitrogen and phosphorus (Tofa et al., 2022). However, NPK fertiliser, which is an important source of these nutrients, has become increasingly expensive (Okojie-Okeiyi, 2025). Reports have indicated that some farmers are reducing maize cultivation because they can no longer afford the cost of fertiliser (AllAfrica, 2025). Compost offers a possible way of reducing dependence on expensive mineral fertilisers. It may serve as a partial substitute or be combined with NPK to improve soil fertility. The use of organic materials among maize farmers in north-western Nigeria has already been documented (Oladimeji, 2020).

Although previous field experiments have examined the effects of organic and mineral fertilisers on maize production, many of these studies were conducted under research conditions using specific materials and application rates that may differ from those available to ordinary farmers (Kareem et al., 2017; Okhumata & Idowu, 2022). Compost can differ considerably in its nutrient composition, depending on the materials used in its preparation. Farmers may also measure and apply compost using locally available containers instead of standard weights, and they may not follow fixed combinations or recommended application rates when using it with NPK. Consequently, there is limited information on the actual combinations of compost and NPK used by maize farmers in Zaria, the quantities and application periods involved, and the growth and yield outcomes reported by the farmers.

This information gap creates practical challenges for farmers, extension workers, researchers and policy makers. Extension agents may find it difficult to determine whether farmers are applying appropriate combinations of compost and NPK or relying too heavily on one input. Farmers also have limited information for comparing their experiences with those of others who use different fertiliser application patterns. Furthermore, researchers and policy makers interested in encouraging compost use or developing fertiliser support programmes lack sufficient information about existing farming practices. Without such information, recommendations may not reflect farmers' actual resources, needs and production conditions.

The problem this study seeks to address is therefore the limited availability of farmer-level information on the patterns of compost and NPK fertiliser use among maize farmers in Zaria Local Government Area and the growth and yield outcomes they report under the different patterns.

1.3 Objectives of the Study

The main objective of this study is to assess the effects of compost and NPK fertiliser on maize growth and yield as reported by farmers in Zaria Local Government Area.

The specific objectives are to:

1. Describe the socio-economic and farm characteristics of maize farmers in the study area.

2. Identify the different patterns of compost and NPK fertiliser use among the farmers, including compost only, NPK only, both inputs, or neither.

3. Examine the quantities of compost and NPK fertiliser applied by farmers and the periods of application.

4. Assess the growth and yield of maize as reported by farmers under each fertiliser application pattern.

5. Examine the relationship between fertiliser application patterns and the yield reported by farmers.

6. Identify the major constraints affecting farmers' use of compost and NPK fertiliser.

1.4 Research Questions

The study will be guided by the following research questions:

(i) What are the socio-economic and farm characteristics of maize farmers in Zaria Local Government Area?

(ii) What proportion of farmers use compost only, NPK only, both inputs, or neither?

(iii) What quantities of compost and NPK fertiliser do farmers apply, and at what stages of maize production are they applied?

(iv) What growth and yield outcomes do farmers report under the different fertiliser application patterns?

(v) Are there differences in the maize yields reported by farmers using the different fertiliser application patterns?

(vi) What are the major constraints affecting the use of compost and NPK fertiliser among maize farmers?

1.5 Research Hypotheses

The following null hypotheses will be tested at the 5% level of significance:

H01: There is no significant difference in the maize yield reported by farmers who use compost only, NPK only, both compost and NPK, or neither input.

H02: There is no significant relationship between the quantity of NPK fertiliser applied and the maize yield reported by farmers.

H03: There is no significant relationship between farmers' socio-economic characteristics, including age, sex, educational level, farm size, farming experience and livestock ownership, and their patterns of fertiliser use.

1.6 Significance of the Study

To farmers: The study will provide information on the different ways maize farmers combine compost and NPK fertiliser and the growth and yield outcomes they report. This information may help farmers compare their practices with those of other farmers, particularly at a time when the cost of mineral fertilisers is increasing.

To extension agents: The findings will provide information on farmers' existing fertiliser application practices and whether they depend mainly on compost, NPK or a combination of both. This will help extension agents identify areas where farmers require additional guidance on soil fertility management and fertiliser application.

To researchers: The study will provide farmer-level information from Zaria Local Government Area to complement existing findings from controlled field experiments. It will also offer useful information on current farming practices that can guide the design of practical on-farm research and future studies.

To policy makers: The findings will provide information on the challenges affecting farmers' use of compost and NPK fertiliser. Such information may support the development of appropriate fertiliser assistance programmes and policies that encourage the use of compost and other organic soil amendments in Kaduna State.

1.7 Scope and Delimitation of the Study

This study is restricted to maize farmers in Zaria Local Government Area of Kaduna State and focuses on the most recent cropping season. It adopts a cross-sectional survey design and uses a structured questionnaire to collect information from respondents.

The study covers the use of compost prepared from crop residues, animal waste and other farm waste, as well as NPK compound fertiliser. It examines the quantities applied, the timing of application, and farmers' reports of maize growth and yield under the different fertiliser application patterns.

The study does not cover the use of urea, organic manure that has not undergone composting, maize varieties, pest management practices or maize marketing activities.

1.8 Limitations of the Study

The study may encounter the following limitations:

1. Inaccurate farmer estimates: Some respondents may not provide precise estimates of the quantities of compost applied or maize harvested. This may occur because compost is often measured with locally available containers, while harvested maize may be sold or consumed before it is weighed.

2. Differences in compost composition: Compost prepared by different farmers may contain varying levels of nutrients because the materials and preparation methods used may differ. Therefore, two farmers applying what they describe as compost may not necessarily be applying materials with the same nutrient content.

3. Influence of other production factors: Since the study uses a questionnaire-based survey, it can identify relationships between fertiliser application patterns and reported maize yield but cannot independently establish the effect of compost or NPK. Other factors, including soil conditions, maize variety, rainfall and farm management practices, may also influence crop performance.

4. Limited time and financial resources: The time and funds available for the research may restrict the number of farmers and communities that can be included in the study.

1.9 Definition of Terms

Compost: Decomposed organic material prepared from crop residues, animal waste and other farm waste and applied to farmland to improve soil fertility and supply organic matter and nutrients.

NPK Fertiliser: A compound mineral fertiliser that supplies three major plant nutrients: nitrogen, phosphorus and potassium. An example commonly used in crop production is NPK 15:15:15.

Growth: The development and physical condition of maize plants, measured in this study through farmers' reports of plant height, leaf colour and general plant vigour.

Yield: The quantity or weight of maize grain harvested from a given unit of farmland, as reported by the farmer.

Pattern of Fertiliser Use: The combination of compost and NPK fertiliser applied by a farmer during the cropping season. The patterns considered include compost only, NPK only, both inputs, and neither input.

REFERENCES

Abubakar, M. I., Idrisa, Y. L., & Pur, J. T. (2022). Preference of extension delivery methods used in the adopted villages of the National Agricultural Extension and Research Liaison Services in Kaduna State, Nigeria. Nigerian Journal of Rural Sociology, 22(1), 16–21.

Akinmutimi, A. L., & Okoroji, M. C. (2024). Effects of organic and inorganic fertilizers on soil chemical properties and the yield of Amaranthus species in a continuously cropped Ultisol. International Journal of Agriculture and Environmental Research, 10(1), 64–74. https://doi.org/10.51193/IJAER.2024.10105

AllAfrica. (2025, July 22). Nigeria: High fertiliser cost – Farmers dump rice, maize cultivation. https://allafrica.com/stories/202507220646.html

Kareem, I., Jawando, O. B., Eifediyi, E. K., Bello, W. B., & Oladosu, Y. (2017). Improvement of growth and yield of maize (Zea mays L.) by poultry manure, maize variety and plant population. Cercetări Agronomice în Moldova, 4(172), 51–64. https://doi.org/10.1515/cerce-2017-0035

Okhumata, D. S., & Idowu, E. R. (2022). Comparative effects of compost–mineral, NPK and urea fertilizer and time of application of compost–mineral fertilizer on the yield of maize. Journal of Wastes and Biomass Management, 4(2), 64–67.

Okojie-Okeiyi, J. (2025, September 10). Farmers shift to cash crops as fertiliser cost jumps 41%. BusinessDay. https://premium.businessday.ng/article/top-story/Farmers-shift-to-cash-crops-as-fertiliser-cost-jumps-41

Oladimeji, T. E. (2020). Effect of soil conservation on productivity and food security on maize farmers in northwest Nigeria [Thesis record]. IITA Research Repository. https://biblio1.iita.org/handle/20.500.12478/7854

Onwubiko, G. N. (2026). Comparative assessment of the morphological traits of local maize (Zea mays L.) varieties upon exposure to varying rates of poultry manure. Current Research in Agricultural Sciences, 13(1), 104–113. https://doi.org/10.18488/cras.v13i1.4944

Tofa, A., Kamara, A., Babaji, B. A., Aliyu, K. T., Ademulegun, T., & Bebeley, J. F. (2022). Maize yield as affected by the interaction of fertilizer nitrogen and phosphorus in the Guinea savanna of Nigeria. Heliyon, 8(11).