The so-called Obeah Bible of De Laurence was mostly copied from the 19th century book The Magus, which itself was largely copied from the works of Agrippa. Though very European in origin, De Laurence marketed his books well in countries like Jamaica and parts of Africa, with the result that his publications and his formulas often supplanted the traditional folk magic of the regions.
There are numerous recommendations about what herbs and colors to use for each sign of the zodiac (you can find some of the alternatives in this previous post) but here are the recommended herbs according to De Laurence's book:
ARIES
Ginseng
TAURUS
Upright Vervain
GEMINI
Bending Vervain
CANCER
Comfrey
LEO
Ladies' Seal
VIRGO
Calamint
LIBRA
Forget-Me-Not
SCORPIO
Mugwort
SAGITTARIUS
Pimpernel
CAPRICORN
Dock
AQUARIUS
Tarragon
PISCES
Pipevine
Zodiac herbs can be used by adding them to spells where a person is being influenced or represented. Find the person's sign and then add the appropriate herbs to the other candles or formulas to enhance the work on them.