I have an idea for a character that involves decay, disease, poison, thorn, fear, and confusion themed magic. A druid or witch seem to be the best fit -- the witch being the easiest of the two to get everything I'd want as far as spells go. However, I want to be able to enter melee combat which limits me to druid.
I decided on a Tiefling Blight Druid. The druid spell list doesn't have very many enchantment spells. I was wondering if there was any way I could gain a few.
The race and class/archetype aren't really negotiable so no Samsaran trait or switching to a Feyspeaker.
Thank you.
EDIT: No third party.
EDIT 2: Is there an item like a Ring of Spell Knowledge for divine casters?
I think it'd be easier to make a witch who can enter melee and matches your theme (e.g. Bloodrager w/undead bloodline 1 / witch w/ strength patron 6 / eldritch knight X) but you say that's set. So...
No, there's no direct divine equivalent to a ring of spell knowledge. However it's possible to get items which create similar effects to spells. For confusion a bewildering weapon may be worth the +1 equivalent, or if you can get an item from an adventure path there's a reaper's mask; nasty item but I'm guessing your concept is evil enough to work with such. For fear, maybe an eye of the void.
Alternately there's a couple of prestige classes which add spells directly to your list. Veiled illusionist (just illusions, but shadow enchantment is a thing) and pathfinder savant. Neither advances most of your druid class features though.