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Today in Romania about 7 mil. ha are affected by drought as a limiting factor for crops. A modern method possibly to be used at farm level in drought conditions is to incorporate superabsorbent materials in soils. These materials have the property to retain water, to further release it in conditions of water scarcity or precipitation lack over a longer interval, especially during the growing season of cultivated crops. The superabsorbent tested in this study is made of maize starch, is structurally made up of solid granules, is biodegradable and non-toxic and have the capacity to retain 500 times more water than their mass. The experimental sites were located in private farms in Pecica, Arad, in fields with oat, onion and water melon crops and consisted of variants in which two doses of superabsorbent were applied (6 Kg/ha and 12 Kg/ha) and a control variant. The volume of soil water at rooting depth that is readily available to plants has a very important role in increasing plant productivity and was measured by determining the soil water retention capacity. Water retention measurements were done on undisturbed soil samples at three depths (5-10 cm, 15-20 cm, 25-30 cm) using laboratory standardized equipments. Measured values of soil moisture are used for calculating the van Genuchten equation parameters and then soil water retention curves were estimated. Study results showed that mobility and availability of water are higher in treated variants than in the control one as a result of superabsorbent application in top-soil layers. Highest values of plant available water were recorded in variant where 12 kg of superabsorbent was applied in oat and onion fields at 15 - 20 cm depth, whereas in water melon field the highest value for available water was determined in variant with 12 kg of superabsorbent at 5 - 10 cm depth. Also it was noticed that in oat field in the variant with 12 kg of Zeba applied, at 15-20 cm depth, in onion field in variant with 12 kg of superabsorbent, at 5-10 cm and 15-20 cm depths and in water melon field in variant with 12 kg of superabsorbent, at 5-10 cm and 25-30 cm depths, the water is strongly retained in soil at lower levels of suction, whereas at pF values higher than 2.5 the water retained in soil starts to be slowly released during the drought periods, when there is no any water supply.