SUMMARY
Nickel is an essential trace element for plants, but excessive Ni levels in the soil can result in toxicity to plants. The aim of this research was to examine the effect of Ni on shoots dry matter (SDM), roots dry matter (RDM) and on Ni concentrations in SDM (Ni-SDM) of mojito and lavender plants. A completely randomized block design with five treatments (0, 5, 10, 20 and 40 mg Ni L-1) and five replications for each treatment and plant species was conducted in pot experiments. Nickel was applied to the pot medium as NiCl26H2O. No visible toxic or inhibitory symptoms were observed on the plants due to the increasing rates of Ni applications. The SDM and RDM were not affected by Ni in the studied plants. Ni-SDM of mojito and lavender raised with increasing rates of Ni above 20 and 10 mg Ni L-1, respectively.