Cumin seeds can be used alone to spice up dishes, or in combination with other spices. Cumin seeds are also known to have medicinal benefits. But farmers have to grow the cumin before any of us can benefit from it. Researchers in Ethiopia recently published a study about using vermicompost to increase cumin seed yields.

Black cumin (Nigella sativa L.) is an annual herbaceous plant grown for its pungent seeds. It’s cultivated in many countries throughout the world including Ethiopia. Despite black cumin’s importance, not much has been done to improve its production and productivity.

Nutrient management is key in creating high yielding cumin fields. The use of organic manures as a substitute for synthetic fertilizer can decrease the cost of production. Among organic manures, vermicompost is being established to create a more sustainable agriculture in Ethiopia. Vermicompost uses worms to mix and process organic waste into compost. This results in compost faster than traditional methods (called thermophilic composting).

Combined fertilizer management in black cumin helps plants absorb and use more nutrients. This can lead to an increase in grain yield and improved nutrition of the seeds.

Ethiopia’s tropical environment is suitable for the growth of black cumin. The researchers evaluated the response of black cumin to different rates of vermicompost and nitrogen fertilizer applied alone or in combination.

They prepared vermicompost from organic materials such as crop residues, animal manures, and ash. They mixed the vermicompost into the soil about two weeks before sowing seeds. They applied nitrogen while sowing and again 40 days after sowing.

The results of the study show good news. The combination of vermicompost and nitrogen treatment increased the cumin plant height and the number of branches on them. The results show that the interaction of vermicompost and nitrogen has significant effects on the number of capsules per plant, number of seeds per capsule, seed yield, and biomass yield.

As the number of branches increase, the capsule numbers per plant also increase. The number of seeds per capsule increased as well, due to the grain filling ability of the black cumin plant when supplied with optimum fertilizer.

Vermicompost plays a vital role in improving soil microbial activities and nutrient availability. These features of vermicompost lead to active nutrient absorbance by plants and hastens growth and development of crops. Nitrogen application also leads to increased nitrogen uptake by plants from the early stages of growth.

The study authors recommend certain application rates of vermicompost and nitrogen, and that farmers in the Guder area of Ethiopia adopt this practice to improve black cumin yields. This blog was compiled by Susan V Fisk from research published in Agricultural and Environmental Letters. The research was supported by Ambo University, Arsi University, and Ethiopian Institute of Agricultural Research Center.

About us: This blog is sponsored and written by members of the American Society of Agronomy and Crop Science Society of America. Our members are researchers and trained, certified, professionals in the areas of growing our world’s food supply while protecting our environment. We work at universities, government research facilities, and private businesses across the United States and the world.