My husband and I are in the process of designing our sustainable farm on 20 acres of our 117 acres. The plan calls for two vineyards, among other plantings. (We have plans for a trout pond, multiple vegetable plots, one or more large berry patches, a fruit and nut orchard, pollinator gardens, and gourmet and medicinal herb gardens.) We want to grow table and wine grapes mostly for our personal consumption, but also for a local food bank and for sale at local farmers markets and to two local wineries. We have a small wine cellar in the lower level of our house and are constructing various outbuildings, one of which might be suitable for harvesting, processing, and making the wine. I have acquired a small library on the topic of vine growing and wine making, but felt I might learn more relevant information from local winemakers who share their experiences in these forums. Cold New Hampshire winters are a challenge, but we are researching technologies to make greenhouses simulate more hospitable climates (zones 6 - 7) in an energy efficient and self-sustained manner.
Welcome!
I do basically what you are planning to do, only on a LOT less than 20 acres. 20 acres of mixed farming will not be easily manageable for 2 people especially if you still have a day job. In fact it will be impossible. Single to just a couple crops are what makes farms efficient, when you deviate from that the demands on your time to care for the individual needs of a single crop x how many other crops you have explodes exponentially. Hopefully you both are still under 45 because if not, that farm will be making you feel your age in 3, 2, 1... It does me.
What I do is. I focus on maybe a half a dozen crops and produce as much of those as I can, but I'm lucky, I get two crop cycles in a year where you only get one. Two seasons doubles my variety for the year. It still kicks my backside and now I'm planning to switch to wine grapes exclusively other than a "garden" for household use now that there are 5 new varieties of wine grapes I can choose from that actually make good Vinifera wine that will survive the wine grape killing diseases endemic to my area.
The first thing I need to know to recommend what wine grapes you can actually grow is what is your average growing season temperature is, because that average growing season temperature determines what grapes you can grow, and I need to know how long your growing season is it because that determines the grapes you can choose from that can actually RIPEN and that's the biggest thing many of those growing books leave out. Wine grape ripening is more of a function of their PH and Brix and degree of veraison than what is required for table grapes to be considered "ripe." Table grapes are ripe when they taste good. That doesn't work for wine grapes.
Knowing what your average growing season temp is and how long it is is more important than the growing zone because there can be drastic differences between average growing season temperatures and growing season length in different hardiness zones. The length of your growing season is best estimated as the time you have between days with an average of 55 degrees and nights above 40. Some use from last spring frost to first autumn frost but this really isn't that good of a measurement to use as many plants will not have significant vegetative growth below a minimum sustained temp of 50-60 degrees. A plant like Brussels sprouts will survive temps in the 40's but it will barely grow in it, it will simply just sit there doing nothing until the weather warms up during the day.
Then I need to know what your lowest night time temp is because that also has a affect on what vines you can grow because vines like Cabernet Sauvignon die below -5. That is basically your hardiness zone.
You probably will not want to try to grow wine grapes in a greenhouse, the demands and cost are prohibitive.
