NE winemaking

My father (84 years old) started to make wine few years ago and to my surprise, he asked me for help this year. I would love to help him but my “experience” is limited to to only few “buckets” of California juice: I’ve never done “grapes” myself. Obviously, there is lots of info in regards to this subject but my father’s “winery” is located in North East. North East means we have very limited number of days until harvest but today’s Brix is around 11 (was 8 last week). So, what should we do:
- Wait for “Brix 20” reading?
- If weather change and we will have to pick grapes up early with Brix 16 or maybe even lower how much sugar should we add? To certain Brix number? What would be the number?
- Should we add grape juice? Maybe other fruits?
And yes, “why bother” somebody may ask? Only, because we (family) will HAVE TO drink it

Where in the Northeast are you located?

What kind of grapes?

Augusta, ME
I don’t know exactly what the grape is but I think it might be Concord

1/8 of a pound (granulated sugar) per gallon will raise must 1 brix. shoot for 21 to 24 brix area.

Agree with REDBOATNY, get the brix up! Do it all the time..

Ok, well if they're concord you have 2 choices. If you really like the fruity flavor of concord---like what Welch's grape juice taste like--then pick them around 14 brix. If you dislike that flavor in the finished wine, then allow them to ripen as close as you can to 16 or 17. I wouldn't wait any longer than that because when concord is over-ripe, it's flavor profile is quite drab.

There is no need to use other juices. Just crush the grapes--set the brix and check PH if you are able to. We like a PH of about 3.4 on concord. Use no water. After it is done aging--12 to 18 months later--if you think the flavor is drab, you can add a couple cans of 100% grape juice to it if you want. Be sure to use sorbate along with meta when sweetening.

Don't be afraid to ask more questions if you need to.