The aim of the study was to establish the beginning date and the duration of each phenological stage of two cultivars of sweet basil, grown as a post-harvest crop in the region of Plovdiv. The study was carried out in the period 2007-2009 in the experimental fields of the Agricultural University – Plovdiv, planted by the block
plot design in four replications, the plot size being 20 m2. After planting of the basil, the soil was fertilized with 16 kg/da of nitrogen incorporated three times until flowering of the second-order branches and irrigation was applied to maintain the 80-100% pre-irrigation soil moisture.
The results showed that third-order branching in both basil cultivars occurred at the same time. The Yubileen cultivar differed from cv.Trakia, the former shooting fourth-order side branches. For Yubileen the beginning of flowering, seed formation and seed maturation in the cluster of the central stem and in the clusters of the first-order to the third-order branches were completed in a shorter period compared to Trakia.