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Vegetation growth is interactively controlled by hydrothermal conditions and the associated biophysiological changes. These factors have experienced dramatic changes over the past decades in Central Asia, where vegetation growth is primarily constrained by soil water availability. However, we have limited understanding of the time scales and the underlying drivers for the responses of vegetation growth to variations in soil water availability between wet and dry periods. Here, we explored the response of vegetation growth to decadal‐scale hydroclimatic variations in wet versus dry periods, during 1992–2015, using remote sensing retrievals of normalized difference vegetation index and multiple climate factors. We discovered divergent responses of vegetation growth to soil water availability, measured by soil moisture content (SM), between wet and dry periods, with spatiotemporally intensified correlation to SM in the dry period. We revealed a unanimous 1‐month time lag in the response of vegetation growth to SM in the dry period, contrary to much longer time lags and a more spatially heterogeneous response in the wet period. The divergent vegetation responses to SM can be largely explained by the variations in hydroclimatic conditions and spring phenology. The intensified vegetation growth‐SM response in the dry period was strongly associated with increased temperature and vapor pressure deficit. Earlier spring phenology exerts a crucial role in mediating the relationship between vegetation growth and SM in the dry period. The complicated interactions between vegetation phenology and hydroclimatic variations should be explicitly considered in predicting regional vegetation growth under a warmer and drier climate regime in water‐stressed regions. Key Points: Vegetation growth responds to soil water availability at much shorter time scales in the dry than in the wet periodsIntensified growth response to soil water availability in the dry period was strongly associated with increased temperature and vapor pressure deficit (VPD)Earlier spring phenology plays a crucial role in mediating the vegetation response to soil water availability during the dry period [ABSTRACT FROM AUTHOR]

Background: Climate manipulation experiments have found lagged responses in biomass and community composition. Aims: To look for lagged responses of flowering phenology and effects on duration of reproductive phases. Methods: Treatment and post-treatment year phenological data from 12 species in a 1-year step warming and double precipitation experiment was examined. Results: Changes in phenology due to the previous year's warming were in the opposite direction to those observed during the treatment year. Six species responded to warming in 2004, delaying flowering 6.2 days and fruiting 7.9 days. Unlike 2003, no species advanced flowering phenology in 2004. Delays resulted from a soil moisture deficit in formerly warmed plots that lasted 3 months or more after warming ended. Increased precipitation altered phenology in one species but did not affect duration of reproductive phases. While 10 of 11 responsive species entered bud phase earlier under warming than in controls in 2003, in only two species showed a phenological delay at the beginning of the bud phase in 2004. Warming tended to shorten flowering and fruiting stages and total duration in spring annuals. Conclusions: Together, these results suggest that climate anomalies can influence phenology in the following year, here due to a lag in soil moisture recharge. [ABSTRACT FROM AUTHOR]