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Soil water availability is a major limiting factor for plant growth in arid ecosystems, which presents challenges for arid ecosystem restoration. Native perennial bunchgrasses are often seeded after wildfire in the Great Basin to prevent the spread of invasive species and minimize soil erosion; however, seeding failure is often attributed to lack of suitable winter precipitation. Seedling emergence and establishment depend on adequate winter precipitation; survival through the growing-season may depend on infrequent, growing-season events that delay soil water deficit and subsequent plant senescence. We investigated how growing-season rainfall events affected soil moisture and possible effects on bunchgrass seedling senescence. We used soil moisture probes to record hourly soil moisture data at two sites (northwestern Nevada and southeastern Oregon) during the second and third year after wildfire. We used soil moisture data to quantify the magnitude of increase in soil moisture and duration of delay in soil-water deficit. Seedling senescence and growing-season precipitation events were measured using regular field surveys and high-precision rain gauges, respectively. The Nevada site experienced average spring precipitation but above-average summer precipitation both years; the Oregon site experienced average rainfall in year two but above-average spring and below average summer precipitation in year three. Across both sites and both years, soil moisture increased at a greater magnitude in response to later growing-season events as compared to earlier season events with similar amounts of precipitation. Summer precipitation events in Nevada had a strong effect on soil moisture and delayed soil moisture deficit until later in the season than in Oregon. The delay in soil moisture deficit corresponded with a delay in seedling tiller senescence, where bunchgrass tillers at Nevada senesced later than those in Oregon in both years. Our results suggest that variation in growing-season precipitation may play an important role in determining seeding treatment effectiveness.