Drainage in the southern part of Roztocze National Park caused intensification of drying which markedly changed habitat conditions. Negative changes were observed in flora of the only peat bog vegetation complex in the Park. The area of raised bogs became smaller, part of them transformed into marshy coniferous forests, whereas some lost its non-forest character. In order to stop unfavourable tendencies in vegetation, complex restoration efforts were made to recreate natural conditions of water circulation and to limit the effects of previous drainage. The results of monitoring conducted from 2000 on permanent plots located in raised bog and marshy coniferous forest indicate the curbing of unfavourable changes in herb layer vegetation observed before. Peat bog vegetation grew stronger and some hygrophilous species expanded onto the area of marshy coniferous forest.