Up to this point, you've made all the right moves: You located and repaired the water or moisture problem in your basement. You scrubbed down the area with Borax and hot water. And you're keeping the area dry, warm and well ventilated by opening the windows and running a fan or dehumidifier. But still, you detect a lingering smell of mildew. With all of these right moves behind you, you have only a few more to make to rid your basement of the mildew smell once and for all. Try one of these smell-busting techniques or try them all until your basement smells fresh and clean, but give each one at least 24 hours to work. You may try these techniques without doing the prep work, but they are more effective if you do.
Baking Soda First
Place some open boxes of baking soda around your basement. One box of baking soda usually has a lifespan of about three months before its odor-absorbing qualities are depleted. With multiple boxes in your basement, you increase the odds of eradicating the smell quickly.
The Cat's Meow
Fill some trays with kitty litter and place them around the basement – unless you have a cat who might use them for his own purposes. In this case, place the open trays in places he cannot access so the kitty litter can absorb the mildew smell.
Vinegar or Lemon Juice
Put the acidic qualities of white vinegar or lemon juice to work on absorbing the mildew smell in your basement. Fill several bowls with either liquid and set them around the basement.
Hold Your Tears
Slice several large onions and place them on plates around the basement. You might run onions under cool water before slicing them and including them in meals, but you want to preserve all the juices to absorb the mildew smell in your basement. -- so do not rinse them.
Make your own scented "mothballs" to eliminate the mildew smell. Combine ½ cup of cloves, ½ cup of peppercorns and four cinnamon sticks, broken into small pieces, in a bowl. Wrap several tablespoons of the mixture in a piece of cheesecloth, muslin or an old pair of pantyhose, securing it with a tie. Place the mothballs around the basement.