The experimental plants of the Florina variety, which had been grafted on the MM106 rootstock, were observed during the 2011-2013 period in the experimental field of the Fruit-growing Department of the Agricultural University – Plovdiv. The influence of the different origin of the rootstocks was analyzed in details (1. from adventive buds located at the root surface; 2. received by means of a conventional technology of micro-propagation; 3. received by a newly applied method of in- vitro propagation by means of somatic organogenesis from leaf explants) regarding the development of the graft in a nursery. The thickening speed of the rootstocks was similar in all three cases in nursery. The rootstock derived by clonal micro-propagation showed slightly higher thickening due to the growth acceleration for a period of one month starting in the middle of June. The natural vegetative growth of the variety slowed down in the middle of July. The natural vegetative growth of the variety began slowing down in the middle of July.