The year of the acid

[GreginND]

With a late spring and relatively cool summer, it is turning out to be a high acid year in North Dakota and Minnesota. Here are the latest numbers from NDSU's test vineyard in Absaraka, ND. Sugar levels are fine but the pH is very low.

Brix pH
1 Bluebell 17.6 2.76
2 Campbell's Early 15 2.85
3 Elvira 13 2.56
4 ES 10-18-75
5 ES 12-6-18 (dirt) 23.4 2.88
6 ES 3-20-33
7 ES 5-4-71 17.4 2.8
8 ES 9-4-72
9 Frontenac 24.6 2.89
10 Frontenac Gris 24.8 2.94
11 GR-7 22 2.95
12 John Viola 22.8 2.78
13 King of the North 20.8 2.66
14 Laura's Laughter 18.6 2.6
15 Leon Millot 22.4 3.07
16 Louise Swenson 19.2 2.97
17 Marechal Foch 23.2 3.03
18 Marquette 25.2 2.66
19 MN 1131 26.4 2.83
20 MN 1200 23.8 2.89
21 MN 1220 23.6 2.99
22 MN 1235 22 2.83
23 MN 1258 24.8 2.8
24 Petite Amie 19.6 2.74
25 Prairie Star 22.4 3.1
26 Sabrevois 19.4 2.84
27 St. Croix 19 2.77
28 Steuben 16 2.42
29 TP 1-1-34 19.6 2.61
30 Valiant 21.2 3.12
31 Worden 14.2 2.54

 

[JohnT]

Perhaps they are all just a little under ripe?

 

[GreginND]

Well, yes. That's the problem. But we could get a freeze at any time. We are behind in GDD's and it is getting late.

 

[JohnT]

I keep a candle burning in my window for you.

 

[grapeman]

We are high in acid here to, but the pH is certainly not as bad as there. pH is actually not bad, but the TA is running a bit high. I find it hard to believe the Marquette is a pH of 2.66 at 25 brix! I have a pH of 2.95 with a brix of 24.

 

[GreginND]

Yes, the numbers are really strange this year. Plenty of sugar in most of these grapes but the acid hasn't dropped much. Marquette from 60 miles east of Absaraka in Hawley, MN was at pH 2.9 and 25 brix last week. I'm picking on Saturday expecting the pH to be over 3.

One factor that might be operative here is canopy management. I don't know how much sun exposure the grapes have had in the NDSU vineyards. And I don't now what trellis they are using.

By the way, number 5 there - ES 12-6-18 - is labeled as "dirt". It actually DOES taste just like dirt. And is a running joke around here as the "dirt" wine. It has some good qualities and is hardy, but the wine is terrible. NDSU keeps growing for cross breeding but none of the winemakers want to take the grapes and vint them.

 

[UBB]

My Marquette (albeit very small harvest) came in at 25 brix and the PH with my meter measured at 3.01

 

[OilnH2O]

Just for comparison, my Leon Millot and M. Foch vines came in at 18.8 Brix, 2.99 pH and TA was 0.90. Similar conditions here, west of the divide, with lots of September rain and cloudy days.

 

[LaughingWaterWine]

GreginND.. I am wondering if you know where I can get frozen Marquette grapes. I am planning on planting this variety and would like to start working with it.
thanks

 

[GreginND]

Unfortunately I doubt you will be able to find any marquette available now. You may want to start talking to growers now to make arrangements for buying some grapes from the 2014 harvest. I don't know of anyone who freezes them and sells them. The 300 pounds I have in the freezer I can't part with.

 

[LaughingWaterWine]

i kind of figured that was the case. thanks i'll start lookin' for next year.