To study a possibility of infection with Legionella at gardening by inhaling of water aerosolized at sprinkling of plants, samples of tap water used for sprinkling of plants grown in outdoor gardens and in greenhouses in the Lublin province (eastern Poland) were examined for the presence of Legionella, along with the samples of soil, artificial medium and air collected in modern greenhouses. The strains of Legionella were isolated from 8 out of 36 samples of water (22.2%) collected from outdoor taps used for sprinkling plants cultivated in outdoor gardens, and from 5 out of 20 samples of water (25.0%) collected from indoor taps used for sprinkling of plants cultivated in traditional greenhouses or foil tunnels. Both in the samples collected from outdoor and indoor taps Legionella pneumophila 2-14 was more common than Legionella spp. (respectively 13.9% vs. 8.3%, and 15.0% vs. 10.0%). No legionellae were found in 18 samples of tap water, 14 samples of soil, 14 samples of artificial medium or 6 samples of air collected in modern greenhouses. The results of this preliminary study suggest that water aerosolized at sprinkling of plants represents a potential source of Legionella infection among gardeners.