Outdoor lysimeter experiments were carried out to elucidate the effect of 4 inorganic and 3 organic salts on60Co and134Cs uptake and dry matter yield of three cuts of clover in the soils of Inshas. A new concept was proposed for assessing the difference in capacity of soil to supply radionuclides to plants as affected by applied inorganic or organic compounds. A relation of plant tissue radionuclide content with time can be expressed in an exponential equation with corresponding regression coefficients. When the same plant species is grown on the same soil differing only in the applied compounds (e.g. Fe-EDDHA, Fe-DTPA, Fe-OAC, Fe(COO)2, Al(OH)3, Ca(H2PO4)2, Fe2O3) the derived equation will change. Differences of either Co or Cs accumulation with time between control and any other treatment were evaluated. The data also show that Fe-DTPA is preferred for60Co as enhancing compound for plant uptake (for decontamination use), compared with other applied salts, on the other hand, any tested salts did not significantly effect134Cs taken by clover. It was also found that more than 70% of the total cobalt uptake was accumulated in the roots which indicate that Co is less mobile in plants than Cs.