Morpho-physiological seedling quality assessment of selected ornamental plant species produced by nurseries in Lilongwe, Malawi

Seedling quality assessment is essential for successful urban landscaping, yet little is known about the quality of ornamental seedlings produced by nurseries in Malawi. This study assessed the morphological and physiological quality attributes of 1,800 seedlings of Codiaeum (Codiaeum variegatum), Roses (Rosa chinensis), and Sheena’s gold (Duranta erecta) from 60 nurseries (54 private, 6 institutional) in Lilongwe, Malawi, using standard quality protocols and two-way ANOVA. Morphological parameters did not differ significantly between nursery types; however, both groups showed high proportions of seedlings with undesirable shoot-to-root ratios and frequent root deformities. Several physiological traits differed between nursery types: private nurseries generally exhibited higher relative water content and chlorophyll concentration, while institutional nurseries showed greater electrolyte leakage, indicating higher cellular stress. Both nursery types produced seedlings with low photosynthetic competency, with maximal quantum yield of PSII (Fv/Fm) values of 0.65–0.66, well below the 0.80 threshold for healthy plants. These findings, together with a companion study documenting systemic management deficiencies and universal potassium deficiency across the same nurseries, reveal that both growing conditions and seedling outcomes are suboptimal. Overall, results caution against relying on any single quality parameter and highlight the urgent need for enforceable seedling quality standards, ornamental-specific benchmarks, and targeted capacity-building programs to support the production of robust ornamental seedlings for urban landscaping in Malawi.