Greenhouse products can be sold retail and appear branded on store shelves, or wholesale to restaraunts, grocers, stalls, nurseries, etc. Retail requires that your products be available storefront, to the public. This means that you'll want your property to be easy to access, and easy to see from the nearby road. Lots of foot traffic or drivebys stop in to make one-off purchases.
Wholesale greenhouses are selling to another business directly, and don't have to worry so much about being attractive to potential customers.
