<p>A sandy, petroleum-contaminated soil had been bioremediated and contained only low levels of heavy hydrocarbons (&lt; 3000&#xa0;mg/kg) but was still severely water-repellent. This soil was treated by alkaline desorption (to remove weathered, amphiphilic, petroleum-like molecules from soil surfaces), plus organic amendment and phytoremediation (using the forage grass <i>Brachiaria humidicola</i>). Over a one-year cycle, field capacity, soil moisture and water-repellency were monitored. During this time, the ratio of In situ Moisture Content/Critical Moisture Content was restored to background levels. This indicated that it was very improbable that hydrophobicity would occur under field conditions, at least not to a degree greater than background. Ten years later, this was confirmed, during critical periods, at the beginning and end of the dry season. This verified that even in the driest part of the year, the field capacity in the treated soil was almost identical to the uncontaminated control (19.96 and 19.23%H, respectively), and the in situ vs critical moisture ratios were equivalent (0.909 vs 0.876 in the treated and uncontaminated control, respectively). Thus, this combination of alkaline desorption, organic amendment and phytoremediation was effective in overcoming the soil deterioration caused by the residual hydrocarbons. Furthermore, this treatment had a long-lasting effect, persisting for more than ten years post-treatment. Additionally, no adverse effects of the alkaline desorption treatment (such as excess salinity or alkalinity) were observed. This is a simple, low-cost method that could be applied in many tropical and subtropical areas with petroleum production, in which this kind of forage species can be cultivated.</p>