During potato desiccation the above-ground parts can be destroyed by mechanical, mechanical-chemical, or chemical methods. In the current study, the mechanical-chemical method was used and instead of chemical compounds natural nonanoic acid (pelargonic acid) was used. Nonanoic acid is a natural active ingredient that can be extracted from vegetable oil (rapeseed oil). It is a short chain fatty acid and a natural product, that fits well with the principles of the Green Revolution, which has introduced restrictions worldwide on the use of chemical plant protection products and promotes natural ones. For comparison carfentrazone-ethyl and glufosinate-ammonium were used. Studies were carried out in Poland during 2012–2014 with the potato variety Ikar, which is known to be among the varieties difficult to desicccate in Poland. The results show that potato leaves were efficiently destroyed by both nonanoic acid and chemicals (carfentrazone-ethyl and glufosinate-ammonium). The level of destruction varied from 94.5% to 99%. The level of stalk drying caused by nonanoic acid was high and it was similar to that of chemical desiccants. None of the studied desiccants significantly affected yield, vascular necrosis or quantity of starch in tubers.