General procedure for the room scents:
Combine the ingredients in a 2 cup (pint) jar or container, or in a pan on the stove top. Cover them with water and heat. The different heating options are explained further down.
Scent #1: Oranges, cinnamon & cloves (allspice and anise are optional).
This scent carries into multiple rooms better, and it can be reheated to scent your rooms for several days.
Scent #2: Lemon, rosemary, & vanilla. It has a lovely freshness to it.
Scent #3: Lime, thyme, mint & vanilla extract. This combination has such a fresh, pleasant scent.
Scent #4: Orange, ginger (fresh or powdered), and almond extract. This is a sweet, delicious scent.
Scent # 5: Pine or cedar twigs (or other fragrant twigs), bay leaves, and nutmeg. These scents combine for a complex aroma. If you have whole nutmeg, use a micro-plane to grate off the outer surface--this will release the scent. Add the whole nutmeg piece along with the gratings.
Make ahead and...
...store in the fridge. Uncooked jars of scented waters will keep in the fridge for 1 to 2 weeks, so you can make these ahead to have on hand. I recommend adding all of the ingredients, including the water, to the jars before refrigerating them.
...freeze them. Freezing them both with and without the water added work fine. Make sure you use freezer-safe jars like these pint wide-mouth mason jars. (Not all mason jars are freezer-safe.)
How to heat the scented mixtures
Some of them provide a more powerful scent than others. Just like the air fresheners you buy, none of these will scent a whole house. Hopefully you already have what you need to try out one or more of these options.
Stove top method.
To get the most powerful scent that will spread to more rooms the fastest. It's easy as can be. Simply combine the ingredients in a pot on the stove, bring them to a boil, and then lower the heat to a simmer. They will immediately begin to scent your kitchen and spread to other rooms. How far the scent spreads depends on the size and layout of your house. The only drawback of this method is that you have to keep a close eye on the water level. If the pan dries out, you'll be smelling burned citrus instead of sweet, fragrant citrus. NOTE: For a stronger scent, simply double or triple the recipe in a larger pot on the stove.
Uncovered Slow Cooker Method.
Use a mini slow cooker--the kind made for keeping dips and sauces warm. The mixture never actually bubbles and visibly steams. It's subtle, but creates a pleasant smell in the house. It's easy and uses very little electricity. If you're concerned about accidentally letting it run dry, you can put a lamp timer on it so that it automatically shuts off at the desired time. Put a scented jar mixture in the microwave for 2 minutes to get it really hot before adding it to the slow cooker. That gives it a jump start on releasing the scent. NOTE: For a stronger scent, simply double or triple the recipe in a larger, full-size slow cooker.
Fondue Pot Method.
If you have a fondue pot, then you have a portable scent station. Set it up in any room you'd like to scent. Get the scent mixture boiling hot before adding it to the fondue pot.
Mug Warmer Method.
It only keeps it warm, it doesn't actually heat it up. So again, be sure to heat the mixture before adding it to the bowl. Or microwave a jar and set it right on top of the mug warmer. This low heat puts off a soft scent that is perfect in a bathroom.
Here's a hint to keep it pretty. As the mixtures cook and lose their color, they're not as attractive. You can spruce it up by floating a fresh slice of citrus on top. Or add a few cranberries; they float and add a touch of color.
Candle Warmer Method.
These work just like the mug warmers. Candle warmers come with a little bowl on top for melting scented candle pellets. Instead, you can add some heated scented water. Or, remove the bowl and set a jar or other bowl on top.
Note: The mug warmer and candle warmer both keep the mixture at about 120°F. That's enough to let off a very subtle scent, but don't expect these to strongly scent a big room. You need more heat and steam for a stronger scent.
Tea Pot Warmer Method.
These only last as long as the tea lights burn, but they can get hotter than the mug and candle warmers, thus releasing more scent.
Add more hot water as needed. As the water evaporates from any of these warming bowls or jars, top it off with additional HOT water. It needs to be hot when it's added so that it doesn't cool down the temperature of the scented water. Higher heat = more fragrance.
Gift them! These make a fun, unique hostess gift. Take one along to a party as a gift for your host that can be simmered and enjoyed the next day.
Reuse each mixture 2-3 times. After these have been heated and simmered for awhile, the water becomes cloudy, and some of the ingredients lose their vibrant color. Although they don't look as pretty, they still smell good. Usually, you can reheat and simmer these again 2-3 times. Jar them up and refrigerate them between uses. Open the jar and give it the sniff test--if it still smells good, reheat and reuse it. Add more water as needed.