The effects of enhanced UV-B are often overestimated in greenhouse studies due to low levels of photosynthetically active radiation (PAR). For this reason, we studied effects of enhanced UV-B (12 kJ m−2 d−1) at low and near ambient PAR levels on young vegetative plants of Vicia faba, in the greenhouse. It was hypothesized that near ambient PAR levels could reduce the negative UV-B effects on growth, due to higher amounts of UV-B absorbing compounds in the leaves and to morphological changes attenuating UV-B damage.