Hi Sharon, thanks for the question. Depending upon what area of the world you live in you can purchase seed through online retailers or your local feed/ag store if you have one handy. The more details you can give them about what the needs of your horses and the type of soil and traffic the pasture needs to hold to the better they can set you up with a seed that will meet your horse’s exact needs. If you are in the US you could check out Nature’s Seed, I’ve worked with them in the past to create custom blends for clients and they are very helpful. They also have a variety of their own blends available that might suit the needs of your horses as well. https://www.naturesseed.com/pasture-seed/horse-pastures