Planning and establishment of urban forests/trees for bio-physical benefits is not new in Nigeria; however, development and management of urban forests/trees for social and cultural values is relatively recent. This study is a diagnostic assessment of all trees/shrubs within University of Benin Teaching Hospital, Benin-City, Nigeria, including the newly introduced indigenous tree species. Ecological analysis was used to describe the relic tree population while ANOVA was used to compare growth in height and mortality of Mansonia altissima, Tieghemela heckelii, Terminalia superba, Khaya grandifoliola, Nauclea diderichii and Piptadeniastrum africanum. There were 224 trees/shrubs – consisting of indigenous (15%) and exotic (85%) – distributed among 27 species, 26 genera and 19 families. Shannon Weiner index (2.65) revealed low species diversity while Terminalia mantaly ranked highest on Important Value Index (IVI) scale. Tree/shrub height ranged 2m to 6m while most stems (68%) recorded <20cm dbh. Ornamental plants (41%) tending toward mature growth stage dominated the landscape. The study revealed that Khaya grandifoliola had a significantly better (P≥0.05) annual growth rate (1.74m) but also recorded highest (62.5%) mortality rate in the urban environment. Relative high growth rates of K. grandifoliola and Nauclea diderichii present a possible alternative to some exotic tree species in urban green spaces.