>>1608235Most farm related websites where you buy seeds in 50lbs bags are pretty good. I found I have to shop around though. One species may cost way more on one site while another species isn't. I'd stay away from amazon sellers who are not specifically the company themselves selling on amazon.
The type of seeds also determines the websites. Flowers/ornamentals will have different websites they are sold on when compared to lawn grass seed or food crops or even fodder crops for animals. For bulk purchases, I'd shy away from organic companies. The only thing you really may want to avoid are systemic pesticides, but chemicals used for enhancing germination rates are normally fine that I know of. The companies with organic seeds are usually way overpriced.
If you buy a mix, like for pastures then make sure it is tailored specifically tot he animals you'll have on the pasture now and in the future. Some things are not good for all animals, horses in particular. So, make sure you can read a listing of all included seeds. Like the product in this image states, "formulated for all livestock," yet it includes some type of fescue (fawn) that I wouldn't want to chance on horses, despite the, "endophyte free," description.
What are you looking for specifically?