That depends on what type of enterprise you're thinking of (selling knowledge, produce, perm products, livestock, etc.) and what type of buyer (individuals, businesses, etc.) and what geographic sales area you have in mind (and channels for sales - e.g. web, storefront, markets).
From there you can figure out segmentation either broadly (e.g. local restaurants seeking herbs) or with more insight and understanding (e.g. individuals engaged with permaculture could be understood in buyer clusters like green thumbs, independence minded homesteaders, moral- or political-based low-impacters, etc.).
You didn't tell me he was so big. Unlike this tiny ad:
Grow Half Your Food - Free Viewing March 20 - From The Grow Network