So far this summer, I have managed to keep a kitchen sponge smelling good for two months. By bleaching? No. By infusing it with biocides? No. By storing it under intense ultraviolet light? No. By inserting a teensy pellet of plutonium I got for my birthday from neighbor Bill that he forgot to turn back in before retiring from the Lawrence Livermore National Laboratory? No.
By rinsing the sponge after every use? Yes.
You see, the only reason a sponge or dishcloth gets to stinking is that there are bacteria on them, and the user feeds the bacteria by wiping up a spill of Bacteria Chow® (which is darn near anything organic) and tossing the damp sponge or cloth onto the drainboard to let it fester. Dampness and food particles make for a stinky sponge. It is so tempting when after all the dinner dishes are done and the counters and tables are wiped clean, you notice just one itsy bitsy spot of gravy or even bread crumbs to wipe up and you’re done. Your hands are dry, the sink and surrounds are spotless, and rinsing the sponge will just mess everything up all over again. Besides, nobody will notice that minuscule spot of stuff on the sponge. Except the bacteria. And they’ll have all night to munch on it and spew poo throughout the sponge.
If you simply can’t stand to get the sink all wet again, toss the sponge in the freezer overnight. Or take it outside, hook it to the line on your spinning rod and tow it behind the boat, making a quick circuit of the lake. Or feed it to the dogs (they’ll eat anything with gravy on it) and buy a new sponge. If you haven’t been rinsing it all along, your old one is probably beyond salvation by now anyway.