For those of us who still have carpeted areas in our house (including myself) we tend to use perfumed products to freshen it up; they are not the best option since all of their functions can be replaced by natural products that you can enhance with essential oils.
You can make a carpet freshener powder by adding essential oils to Baking Soda or Borax Powder. For each tablespoon of powder, add 1 drop of your choice of essential oil to the powder and mix well. How much you make depends on your requirements. Store in a tightly sealed jar overnight and then sprinkle on your carpet and leave for a few minutes before vacuuming.
Good Bacteria Buster essential oils are:
Cinnamon, Pine, , Thyme, Grapefruit, Lemon, Eucalyptus, Lavender, Lime and Clove. Take your pick!