From the official boards awhile back.

I have herb/alch at the moment
For me Herb has made me TONS of gold.
I always try to have 250+ Gold to help the guildies

Since you're level 59 you will have no problem starting herb from the start and getting it 300 easy.

The best way to make money for herb is to farm these following herbs in a few hours

Goldthorn
Fadeleaf
Blindweed

I've farmed 15 stacks of goldthorn one day and selled each for 5g ( Very cheap price on my server ) and I just made money in an hour or so.