Technology regarding grafted walnut production is very complex and expensive because it depends on a number of factors that directly influence grafting success. Due to a long production period and a smaller number of first class plants compared to other fruit species, young walnut trees are among the most expensive. New in situ production technology of young walnut trees has led to quicker production, shorter by 1 year, and increased the success of grafting, allowing for large-scale production of grafted walnut. In order to increase the production of quality planting material for walnut varieties, the possibility of walnut grafting in the open, i.e. in situ, was examined herein. Based on the average results for all of the varieties/selections, similar performance was achieved with grafting (57.14%) and the number of first class plants (55.71%) when compared to conventional grafting (54.46% and 53.39%, respectively), but it was concluded that this method shortened the process of plant production for 1 vegetation. The greatest success with the application of in situ grafting was with the Rasna selection, which had significantly the best grafting take (72.86%) in comparison with the other walnut varieties examined during the research period. By comparing the success of the indoor and in situ production methods and examining the influence of certain factors on production success, it was concluded that the in situ method proved to be a better option for a simpler, more profitable, and faster mass production of high-quality walnut planting material.