Off the top of my head I thought of these:
Calendula and Chamomile are of the aster-family (like Echinacea). Their blossoms are orange or yellow (Calendula) and white (Chamomile).
In addition to looking cute, both are well-known healing plants that should have their place in every herbal garden.
Chamomile is known as that type of tea you should drink when you are sick with a cold or have an upset stomach. It helps reduce inflammation and can be used in ointments for the skin. Also good as mouthwash to aid healing of open wounds in the mouth area. A tea with Chamomile and Lavender before sleep can help relax.
Calendula has much of the same properties although it is often used in (natural) skin care products. Aids in healing wounds (do not put in/on fresh/open wounds!) and helps irritated skin.
Then there is Tropaeolum majus (Nasturtium, but the one with the bigger blossoms in orange and yellow). The blossoms and leaves can be used in salad, it is a bit peppery/spicy tasting. The plant has been found to act antibiotic/antimycotic and to help with bladder infections.
I would also suggest to look for books about herbal remedies, there are many suggestions online.
Just be careful to always research before you use a plant for anything or if you got the right type of plant. 🙂 🌼
(Note: I am not a doctor nor do I suggest herbal remedies can replace proper consultation by a trusted doctor.)