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Abstract Background Fire is a critical ecosystem process for maintaining savannas globally, but how it affects tree growth is complex. Climate, a dominant driver of tree growth, may interact with fire to produce novel climate-growth relationships because of the way climate influences fire intensity and the role it plays in facilitating post-fire tree recovery. Understanding how fire and climate interact to influence tree growth is critical for managing longleaf pine ( Pinus palustris ) savannas, a fire-dependent ecosystem undergoing rapid environmental change. Results We analyzed annual basal area increment (BAI) from 453 longleaf pine tree core samples collected across eight sites spanning three community types in Florida to quantify how monthly and seasonal climatic variables influence tree growth, and how these relationships are modified by fire and fire seasonality. We found that maximum temperature and precipitation during late spring and summer and summer to fall PDSI were key drivers of growth, but their effects varied by site and were frequently altered by the occurrence of fire. Notably, at four of eight sites, fire reversed the direction of climate-growth relationships. Reversals are when a positive climate effect in non-fire years becomes negative in fire years, or vice versa. Reversals most commonly changed the effect of climatic variables on tree growth from positive to negative, though the direction varied across sites and seasons. Fire also strengthened the effect that climate had on growth at four sites. Tree growth was slightly reduced in fire years regardless of the season of fire, but these differences were not statistically significant, suggesting overall resilience of longleaf pine growth to fire occurrence. Conclusions Our findings show that tree growth in frequent-fire systems is shaped by complex interactions between climate and fire, and that fire can mediate or even reverse the effects of climate. Importantly, individual tree responses varied significantly across and within sites, pointing to high intraspecific variability likely driven by individual tree characteristics (size and age) and local site conditions including competition and management legacies. By incorporating individual-level growth data, this study underscores the need for fine-scale, context-specific fire management strategies that account for local climate and ecological variation across the longleaf pine range.