The growth of maize (Zea mays L.), hybrid Valentina, was compared in two types of contaminated soil substrates (Ochre and Heap) with different arsenic (As) concentration originating from an old mining area in Slovakia. Although the total As concentration in Heap soil was 2.6 times lower than in Ochre soil (90 and 237 mg kg⁻¹, respectively), plants grown in Heap soil accumulated more As in their tissues (shoot and root As concentration being 4 and 5.5 times higher, respectively) and were markedly smaller, which produced significantly less biomass and flowered later in comparison with Ochre soil grown plants.