<p>Field experiments were carried out using <em>Helianthus annuus</em> in an attempt to improve the quality of soil conditions by application of industrial waste. A range of quantities of olive core, olive core ash and a mixture of the two kinds of waste were applied. In all experimental fields the plants reached their maximum height on the 80<sup>th</sup> day of their growth. The application of olive core increased the plant height and decreased the soil pH, suggesting an increase in the nutrient element bioavailability. There was also evidence that olive core increased the soil microbe biomass. Furthermore, olive core woodash gave the dry biomass of <em>Helianthus annuus </em>a boost.</p>