Water availability and higher temperatures are the major ecological factors affecting plant metabolism in arid systems. The current study explores the combined effects of water availability at three levels (6, 12, and 18%) and higher temperatures on the plant attributes of Senna italica. To understand this, we grew S. italica plants in the net house and under natural conditions during the hot summer of Fujairah. According to our results, the root length of plants growing under field conditions was positively affected by the drought and temperatures. Contrary, more biomasses were allocated to the shoots of those growing in the net house. Survival rates were significantly lower for plants growing in the field. Minerals assessments revealed that plants growing in the field had greater values of calcium, magnesium, and potassium, whereas those of the net house showed more phosphorus, zinc, tannin, ash, carotenoids, and flavonoids. We found higher zones of inhibition 14.33, and 14 mm against E. coli, S. aureus, and C. albicans for plant root growing under natural conditions. The present study indicates that S. italica could be a model plant for land degradation restoration in the desert regions. This study also indicates that plant metabolites resulting from higher drought stress might be beneficial for pharmaceutical uses.