Native Plants Can Strengthen Urban Green Infrastructure: An Experimental Case Study in the Mediterranean-Type Region of Central Chile

In Chile Santiago, urban plants are highly vulnerable to drought, as they are mainly exotic from the northern hemisphere with temperate origins. We hypothesize that, although species may generally differ in their response to water restriction, we would find high growth and survival rates among native species of central Chile. The goal was to determine the effect of the year season and an irrigation gradient on the growth and survival of native plant, in order to evaluate potential plant for use in urban green areas of central Chile. Four plots of 20 m2 were located in the Santiago center. In June 2024 twelve species were planted and from November 2024 to March 2025 were irrigated with 13.3, 10.1, 1.7 and 1.4 L/m2/day in each o the lots. The GLM and Kaplan-Meier survival analyses were used. Shoot growth rate was highly variable among species, among irrigation treatments applied, and among year seasons. Eight species shown water-related growth and shoot growth during the winter was very small and higher in spring. Two species showed evidence of water-related survival; in the other 10 species, no significant differences were found between irrigation treatments. Winter was the season with the highest survival rates for eleven species. In conclusion, the evidence suggests that using native species with low water requirements is an effective and efficient way to use water in the urban green area of central Chile.