I am an environmental studies major and I have serious health issues. I willingly pay a premium for food to keep me out of the ER. I am hardly the only one. I met one guy online who grew a garden to have control over food quality for his wife, going so far as to test the soil and amend the soil to get the nutrient content he wanted. It did make a difference with her health issue.

You could market this as environmentally sustainable for people concerned about that issue. You could also market it as something that lets you grow your own organic health foods.

As for the small spice thing, that is a great place to start. Organic spices are quite expensive. You can briefly note it will pay for itself over time but frame that as a "bonus". The appeal for people willing to buy organic is that this the freshest possible spice, picked from the vine mere seconds before adding it to your recipe. Having it in your kitchen means it is fresher than anything you coukd bring in from the back yard.

I have known people who grew their own cilantro to use it as an alternative treatment. These are the type of people who would buy something like this. You would be in the business of making it easier to be a control freak defending themselves from living in a toxic world and also in the business of making the world less toxic by letting people grow their own locally, eliminating transport pollution, eliminating chemical fertilizer, etc.