Organic fertilization systems on the vegetative growth and essential oil production of Pelargonium graveolens

The aromatic plant Pelargonium graveolens L. 'Hérit, known as geranium, presents bioactive compounds of high economic interest. Since the secondary metabolism is affected by several factors such as the cultivation conditions, this work aimed to assess the impact of different fertilization systems on geranium vegetative growth and essential oil content and yield. The treatments were: T1) chemical fertilization (N-P-K); T2) no fertilization; T3) biodynamic fertilization; T4) organic fertilization; T5) biodynamic fertilization + plant growth-promoting bacteria (PGPB); T6) organic fertilization + PGPB; and T7) organic compost. The application of Azospirillum brasilense (PGPB) had no significant effect on geranium vegetative growth and essential oil production. Essential oil production was not observed in plants treated with chemical (T1) or biodynamic fertilizers (T3 and T5). Plants treated with organic fertilization (T4 and T6) showed greater agronomic development in addition to essential oil content and yield. Consequently, organic fertilization emerges as a promising approach for cultivating P. graveolens.