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The addition of organic amendments and mulches to degraded soils is a common soil restoration strategy in calcareous quarries that has generated proven benefits in subhumid and semiarid environments. We evaluated their effects in a quarry located in SE Spain in an area of transition from arid to semiarid climate. Amendments consisted of sewage sludges from an urban water treatment plant and compost from urban organic wastes. Mulches consisted of siliceous fine gravels and woodchips. Effects on 3 native species (Macrochloa tenacissima, Anthyllis terniflora, and Anthyllis cytisoides) planted in 9 experimental plots (75 m(2)) were tested in a two-way crossed design. Plant monitoring consisted of survival and growth assessment at months 6, 24, 36, and 48, and these results were related to the main soil properties and the hydrological behaviour by means of principal component analysis. The response to soil treatments of each plant species was different due to its own physiology: M. tenacissima had the highest average survival rate, 92%, although both Anthyllis species presented the lowest rates, that is, 15% and 36%, in A. terniflora and A. cytisoides, respectively. Plant growth was favoured by both organic amendments and especially by compost, which improved the hydrological soil behaviour. Conversely, mulches did not show effective results. Run-off and soil loss were associated with treatments without amendment and without mulch or treatments with gravel mulch. Our results suggest that organic amendments, especially by improving the hydrological response, can create favourable conditions for revegetating with native species in restored mine soils.