Herbs are often worn or carried in order to tap into their specific powers.  Following are several traditional herbal amulets, some of which are questionable, some fanciful, but all facinating and potentially useful.

 

To see ghosts: Carry lavender and inhale it's scent

 

To allay fear: Carry  a mixture of nettle and yarrow

 

To avoid military service:  Wear a four-leaved clover if you wish to avoid duty.

 

To ensure safety and protection on a journey: Comfrey worn or carrired will safeguard you.

 

Taken from the Secret Craft of the Wise Magical Herbalism by Scott Cunningham