Grape pomace's potential on semi-arid soil health enhances performance of maize, wheat, and grape crops

Isaac K. Mpanga, Günter Neumann, Judith K. Brown, Joseph Blankinship, Russell Tronstad, Omololu Idowu

Research output: Contribution to journalArticlepeer-review


Background: Grape pomace (GP) is a by-product of wineries after filtering the grape juice for wine production. GP contains seeds, pulp, skin, and stalks with acidic properties, and it is normally composted before using as a soil amendment. However, composting GP requires more time, labor, and equipment; furthermore, composting loses some of the desirable organic acids for arid soils. The acidic properties of these organic acids and the plant nutrients in GP make it a desirable amendment for arid soils in both non-composted and composted forms. Aim: This study investigates the potential of directly applying GP as a soil amendment and its impact on arid soil health and plant performance. Methods: To test the potential of non-composted GP as a soil amendment, greenhouse and field studies were conducted by combining GP with existing management practices (manure application for soil used in the greenhouse study and fertigation for the field study) to assess the effects of GP on soil health and crop (maize, wheat, and grape) performance. Results: Adding 5% GP to an alkaline soil significantly increased maize and wheat growth and shoot nutrient concentrations in the greenhouse and grapes in the field (48% yield increase). The significance of GP on maize, wheat, and grapes was associated with soil nutrient enhancements (i.e., nutrients supplied, increase in organic matter and microbial biomass increase, reduction in pH, and better nutrient mobilization). Conclusion: GP has the potential for direct use as a soil amendment for soil and crop health improvement, especially in arid soils with high pH and limited soil organic matter.

Original languageEnglish (US)
Pages (from-to)276-285
Number of pages10
JournalJournal of Plant Nutrition and Soil Science
Issue number3
StatePublished - Jun 2023


  • grape pomace (GP)
  • soil health
  • soil pH
  • sustainable agriculture
  • waste

ASJC Scopus subject areas

  • Soil Science
  • Plant Science


Dive into the research topics of 'Grape pomace's potential on semi-arid soil health enhances performance of maize, wheat, and grape crops'. Together they form a unique fingerprint.

Cite this