This meta-analysis examines the generality of local adaptation in plants and the factors influencing it. Local adaptation, where plants perform better at their site of origin than at other sites, is crucial in evolutionary, population, conservation, and global-change biology. The study uses data from 35 published studies involving 32 plant species and 1032 pairwise comparisons of local and foreign plant populations. Key findings include: 1. **Overall Performance**: Local plants outperformed foreign plants at their site of origin in 71.0% of the studied sites. 2. **Strict Definition of Local Adaptation**: Local plants performed better at both sites in 45.3% of the compared population pairs, indicating divergent selection. 3. **Population Size**: Local adaptation was more common in large populations (>1000 flowering individuals) than in small populations (<1000 flowering individuals). 4. ** Independence of Local Adaptation**: Local adaptation was independent of plant life history, habitat characteristics, and geographic scale. 5. **Geographic Distance**: The strength of local adaptation was not significantly associated with geographic distance, but variation in adaptation was greater at smaller geographic scales. The study suggests that local adaptation is less common than generally assumed and highlights the importance of population size for evolutionary theory. Small populations are less likely to adapt locally due to reduced genetic diversity, increased inbreeding, and higher risk of maladaptation. These findings have significant implications for the ability of small plant populations to cope with changing environments.This meta-analysis examines the generality of local adaptation in plants and the factors influencing it. Local adaptation, where plants perform better at their site of origin than at other sites, is crucial in evolutionary, population, conservation, and global-change biology. The study uses data from 35 published studies involving 32 plant species and 1032 pairwise comparisons of local and foreign plant populations. Key findings include: 1. **Overall Performance**: Local plants outperformed foreign plants at their site of origin in 71.0% of the studied sites. 2. **Strict Definition of Local Adaptation**: Local plants performed better at both sites in 45.3% of the compared population pairs, indicating divergent selection. 3. **Population Size**: Local adaptation was more common in large populations (>1000 flowering individuals) than in small populations (<1000 flowering individuals). 4. ** Independence of Local Adaptation**: Local adaptation was independent of plant life history, habitat characteristics, and geographic scale. 5. **Geographic Distance**: The strength of local adaptation was not significantly associated with geographic distance, but variation in adaptation was greater at smaller geographic scales. The study suggests that local adaptation is less common than generally assumed and highlights the importance of population size for evolutionary theory. Small populations are less likely to adapt locally due to reduced genetic diversity, increased inbreeding, and higher risk of maladaptation. These findings have significant implications for the ability of small plant populations to cope with changing environments.