I have the Dutch Formula nutrients, the complete line (Grow, Bloom, and Micro) stored for about 5 or 6 years, can I still use them or do you think they've lost their effectiveness? They don't indicate an expiration date anywhere.
try to open grow and check is it still has any ec value, mix in needed proportions and check, i never worked with that line, so no check points, but i think internet is full of, just google ...
Happy Growing !!!