Soil Experts Warn Farmers on Fertilizer Overuse

Nairobi: Kenyan farmers have been cautioned against the overuse of synthetic fertilizers, with experts warning that decades of heavy reliance on chemical inputs are steadily eroding soil fertility and reducing productivity.

According to Kenya News Agency, soil expert and CEO of Pure Plant Organics, Dennis Murithi, said continued dependence on synthetic fertilizers poses a serious threat to soil health and long-term food security. Murithi explained that while synthetic fertilizers provide a quick boost, they ultimately strip the soil of its natural structure and nutrients.

Murithi noted that degraded soils struggle to retain water, support strong root systems, or resist pests and diseases, which ultimately leads to lower yields. He further warned that overuse of fertilizers kills beneficial microbes, compacts the soil, and disrupts its natural balance. This results in farmland that appears productive in the short term but becomes fragile and vulnerable to pests, diseases, and environmental stress in the long run. If unchecked, this degradation can become irreversible.

Murithi stressed that soil degradation risks triggering a food security crisis, as reduced yields mean less produce for markets, higher costs for farmers, and fewer resources for communities. He explained that once the natural balance of soil is lost, crops cannot access water or nutrients effectively, even with irrigation, which poses a national food security issue.

To avert this crisis, Murithi advocates for a gradual shift towards organic farming practices. He urged farmers to reduce synthetic fertilizer use and adopt organic alternatives such as compost, organic fertilizer, and soil amendments. He emphasized the use of agricultural residues like maize stalks for mulching or converting them into organic fertilizer through pyrolysis to restore soil health.

Murithi underscored that their approach focuses on amending the soil, not just feeding the plants. By improving aeration, water retention, and nutrient balance, they help soils return to their natural fertile state. He noted that healthy soils produce healthy plants, which in turn guarantees food security.

With unpredictable rainfall and longer dry spells, Murithi stated that organic fertilizers help soils retain water, enabling crops to withstand harsh weather conditions. Organic fertilizers work with nature, not against it, supporting root growth and improving nutrient absorption. He added that high-value crops such as avocados, tea, coffee, and vegetables can thrive under organic management.

Murithi’s company, Pure Plant Organics, now produces organic fertilizers and soil amendments aimed at restoring soil fertility while supporting sustainable farming practices.