This is an experimental turkey brine. Normally brine for 12 to 24 hours, then season (with a simple dry rub) for another 12 to 24 hours. Then cook your turkey the best you know how (deep-fried is preferred).
Stir vegetable broth, water, salt, pepper, sugar, garlic powder, thyme, and rosemary together in a saucepan over medium heat; bring to a boil. Cook, stirring regularly, until the salt and sugar are dissolved, about 5 minutes. Cool completely.
Mix brine and ice together in a large container.
Always brine foods in a food-grade, nonreactive container such as a stainless steel or enameled stockpot, a brining bag, or a food-grade plastic bucket. Never use ordinary trash bags, plastic trash cans, or metal buckets or containers not meant for food use.