Drought, salinization and heavy metal pollution of soils are main stress factors with an increasing impact on the deterioration of soil quality, yield and crop quality. Seed priming shows good results in improving seed germination, seedling growth and plant development. Proline (Pro) and metyl jasmonate (MeJA) show stimulating activity and help plants overcome stress. The study investigated the effect of Pro, MeJA and hydropriming on seeds sown on water agar supplemented with different concentrations of heavy metals (Cd, Pb, Zn) (HM), NaCl or Polyethylene glycol 6000 (PEG 6000). Chelidonium majus is a medicinal species which is grown as a crop in some parts of Europe. It is an ingredient in some remedies and is becoming an increasingly popular object of research regarding its biological activities. The low concentrations of all heavy metals applied increased the germination of all variants of seeds – control, hydroprimed and those which were Pro and MeJA primed. Seed priming with Pro and MeJA promoted high germination percentage of seeds germinated on water agar with NaCl. PEG 6000 at its higher concentration (5%) slightly increased the seed germination of all variants. The growth of roots and hypocotyls was inhibited by HM and NaCl. However, PEG 6000 slightly influenced their growth.