There are currently as many definitions of energy medicine as there are teachers and practitioners of various types of it. All of those understandings, however, have something to do with healing that is effective, yet operates by means that are neither apparent to our ordinary senses nor currently understood by mainstream medicine.
Acupuncture, homeopathy, flower essences, and various types of "energy healing" are all included as examples by Richard Gerber, M.D. in his important book Vibrational Medicine; "vibrational medicine" is another term for "energy medicine."
The energy medicine that's called "flower essences" is something like homeopathy, but it is not the same. You may be familiar with the Bach Flowers from England - those were the first flower essences in the modern era, but now there are many more, from all over the world. Flower essences can be helpful at all levels of the person, but they are most commonly used to assist with emotional issues.
(The energy medicine that uses "flower esences" is different from the herbal medicine that uses "essential oils"; that modality is commonly called aromatherapy.)
Judy Steele, MTP, uses homeopathy, flower essences, acupressure (a specific type called Tapas Acupressure Technique), and such energy transmission techniques as Reiki and sound healing in her work with clients. She uses these approaches because over many years of experience she has found that they are quite effective in assisting people to heal and grow.
See also Energy Psychology.