The main goal of the work is to validate ion-exchange substrates as optimizers of plant mineral supply within bio-engineering systems of life support with a high level of closure. Test objects were spring Lisovsky wheat-232 and leaf cabbage Sensuji-kyomizuna. Crops were cultivated on artificial soil (AS) in environmentally controlled plant growth chambers. Prior to seeding, AS was enriched simultaneously with wheat straw and ion-exchange substrate BIONA-312 to the extent of 2, 10 or 20% of AS dry mass. Incorporation of the ion-exchange substrate in the amount of 10% increased crop productivity and eliminated the negative effect of wheat straw. Ion-exchange substrate in amount of 20% did not yield a noticeable gain in productivity as compared with the previous test.