Valorisation of Composted Spent Coffee Grounds as a Sustainable Peat Substitute to Enhance Growth and Visual Quality of <i>Dieffenbachia amoena</i>


ÖZDEMİR S., Ozer H., Eren B., Ozdemir S.

NEW ZEALAND JOURNAL OF CROP AND HORTICULTURAL SCIENCE, cilt.54, sa.3, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 54 Sayı: 3
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1002/nzc2.70232
  • Dergi Adı: NEW ZEALAND JOURNAL OF CROP AND HORTICULTURAL SCIENCE
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Periodicals Index Online, BIOSIS, Geobase, Academic Search Ultimate (EBSCO), Natural Science Collection (ProQuest), Biomedical Reference Collection: Corporate Edition (EBSCO), Engineering Source (EBSCO)
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

This study explores the reutilisation of spent coffee grounds (SCG) in the horticultural sector as an eco-functional additive to develop innovative growing media that enhance the propagation of stem cuttings. Raw SCG underwent composting and resultant mature compost was subsequently blended with commercial potting mixes at 0%, 12.5%, 25% and 50% ratios to evaluate their effects on plant establishment, vegetative growth and visual quality. After 6 months of growth, plant height and visual quality were evaluated using digital image analysis based on CIElab colour features. The mature SCG demonstrated elevated levels of functional components beneficial for plant growth, including significant concentrations of humic and fulvic acids, essential macro- and micronutrients and rooting hormone-like substances. Substituting peat with SCG in the growing media significantly improved growth metrics for Dieffenbachia, encompassing increased plant height, leaf count, area and chlorophyll concentration. Image analysis executed in the CIElab colour space revealed that the SCG-treated samples exhibited significantly enhanced brightness (L*) and chromatic values for green-red (a*) and blue-yellow (b*) compared to controls (p <= 0.05). The findings substantiate that composted SCG promotes vegetative growth and improves visual characteristics in Dieffenbachia. Furthermore, MATLAB-based image analysis provided a useful complementary, non-destructive approach for quantifying treatment-related differences in plant colouration and visual characteristics.