What are ecotypes adapted to? Insights from common garden experiments across geographic gradients

Common garden experiments can be used to recognize ecotypes from across the range of a species with a view to identifying sources suitable for restoration. However, simply growing plants from different sites in one location provides limited insight into the drivers of ecotypic adaptation. We contrast inferences drawn from a multi-garden common garden experiment, along with a common garden experiment that included soil manipulation to highlight the need to manipulate more than just source populations to determine mechanisms behind ecotypic development.