Hi David. To answer your question, there are a few bits of info necessary. And as for food or flowers, that again depends on your answers to the questions below.
What size green house are you hoping for?
How much ground space do you have available?
Are you looking for building plans or a prefab kit?
What is your winter night low temperature?
What heat source is available?
Will it be used for hydroponics or soil grown plants?
