Scented Herbs for the Bathroom

I just wanted to know what herbs are nice and scented to be placed in a bathroom, that has a nice clean scent.

There are many herbs that are used in potpourris. Potpourris are blends of herbs kept in an open container such as a decorative glass bowl that allows scents to escape to fill the room. Some of the more popular potpourri herbs are lavender, rose petals, lemon verbena, scented geranium, mints, and jasmine. Essential oils are added to enhance the scent and usually a fixative – a substance that helps to 'fix' or hold the scent – is added also. Powdered orris roots or powdered calamus roots are two common fixatives.
The most common type of potpourri is the dry potpourri: all the ingredients except the oils are added to the mix in the dried form. Less common is the wet potpourri where fresh herbs are mixed with salt to form an aromatic caked mass.
You can make your own potpourris following the directions in a book such as "Making Candles & Potpourri" (available from Richters; see www.richters.com/Web_store/web_store.cgi?product=XB6192). You can use plants from your garden or you can assemble the ingredients yourself. Or you can get our potpourri kit (https://www.richters.com/Web_store/web_store.cgi?product=XT5500) which comes with the herbs, spices, flowers, essential oil and fixative needed to make your own potpourri.

And also do garden herbs have to planted in the earth or can I keep them planted in a pot or such?

Many herbs will grow either way. But there are many that do best in the garden, while others are better in containers because they must be brought indoors over winter.