At a very basic level, terpenes are the molecules in a plant responsible for its aroma, but there is so much more to terpenes than meets the nose.

Just over 400 known terpenes exist in the natural world, nearly half of which have been found in the  cannabis plant, making hemp one of the most terpene-rich species in the Plant Kingdom. Through mere coincidence, shared evolution, or sheer providence, the terpenes in hemp work in tandem with cannabinoids to produce many medical benefits to humans.

So if you’re growing hemp as a medicine, it’s wise to pay attention to the terpene profile of your crop, says hemp breeder Joe Ullman of Atlas Seed Co. and guest on this week’s podcast. This is a deep dive on terpenes – what they are, how they work, and why you should care.

Joe also shares his top 10 list of terpenes – what they’re good for, what they smell like, and what other plants they’re found in.