Grapes don't like to be cold. Grapes don't like to be wet. In short, grapes don't like New Hampshire, or they shouldn't. But with the advances in French hybrids, Granite Staters can make their own private vineyard as good as any more congenial ecosystem.
However, it's important to note this not a hobby for the faint of heart. It takes patience — five years of patience to be exact — in order for grapes to be ready to make wine. Also, even northern grapes are a bit picky. So things like placement, drainage and soil quality matter.
The most important thing about growing northern grapes is that your rootstock has to be perfect, said Amy LaBelle, winemaker at LaBelle Winery in Amherst.
"If you don't select rootstock that can grow in New England, you will fail. Period. So you have to select cold-hardy grapes," she said.
This used to mean only grapes like Concord, which most winemakers agree is best left to jelly. But recent advancements in cold-hardy grapes have produced good quality wine grapes.
"For example all of the grapes on our property are good to 29 degrees below zero," LaBelle said. "Whereas Cabernet Sauvignon — which is maybe the most popular grape, one of the most well-known grape — is only good to 10 or 12 above zero. So, it would get wiped out every year. It just couldn't survive here. So it's not our summers that's the problem, it's the winters."
The grapes that grow around these parts are French hybrids, said Bob Manly, co-owner of Hermit Woods Winery in Sanbornton. Manly said since most people aren't necessarily familiar with those grapes and what they taste like, he encourages those looking to plant their own to tour some wineries to really learn about the grapes and the wines they make.
"Most wine makers are usually pretty eager to share what worked for them and what didn't," Manly said.
Next, pick a good site. Remember, grapes are finicky and truth be told, it's best that the soil is prepped a year in advance, according to the University of New Hampshire Cooperative Extension. (Unless, that is, the homemaker just wants to cover a nice arbor in his or her backyard with vines and in five years have enough grapes to make wine. If that's the case, Manly said, plant a vine or two on either side of the arbor and in five years, the winemaker will have his or her wish.)
For those interested in this as a hobby or business, there's some prep work that needs to be done.
The soil itself needs to be well-drained and sandy, although other soil types can be amended to make a nice environment for grapes. Because grapes like well-drained soil, they do well on hillsides, LaBelle said. The land should have a rise of at least five feet in every 100 feet.
"If you've got a boggy meadow," LaBelle said. "You're not going to be able to grow grapes very well."
The slope should also face south/southwest to give the grapes the best head start, LaBelle said. It's also good to get the soil tested to check its pH, which can be done through the UNH Extension.
According to the UNH web site, grapes will do best on a, "well drained loam soil with a pH of 5.5 to 6.5." Further, they recommend a site that seldom experiences winter temperatures below -5˚F or late spring frosts and has a frost-free growing season of at least 165 to 180 days.
Once the site and soil are sorted out it's time to move onto picking out the actual plants. First, figure out production. Legally, a home winemaker can make up to 200 gallons a year for personal use. The rule of thumb is that a single vine will produce enough grapes about one bottle of wine, once it comes to fruition.
Manly said it's a good idea to buy one-year-old vines which already have a root ball on them.
"You have the best success starting from those," he said. "There are a number of dealers in the Northeast that specialize in those types of vines."
LaBelle also suggested soaking the roots in water and root stock stimulator. She said this perks the roots right up and gets them really hydrated before planting.
The plants should be spaced 8 feet apart in rows 8 to 10 feet apart, according to UNH and soil should be packed firmly around the roots. Newly-set plants should be pruned to a single cane.
In the first growing season, shoots that develop need to be tied loosely to a stake. After that, it's important to trellis the grapes. The trellis system is made up of firmly-set, well-braced posts at 10-to-15- foot intervals along a row. Two strands of wire are attached to the posts one at roughly 5 feet and one at 3 feet from the ground. Well-braced end posts should be set in the ground at least 3 feet deep
Don't fertilize too much, experts said, otherwise the winemaker may get too vigorous of growth.
LaBelle said some vines may be so happy that they will start to push fruit in the first year. If that happens, they should be cut back. And Manly said a vine typically will produce more grapes than you want, which is why wine grape growers will cut back the grapes in the first year of production.
"You don't want the carbohydrates to go into the grapes," LaBelle said. "You want the carbohydrates to go into the root development and shoot development."
The first year, the grapes are cut and used for compost; the second year is selective cutting. Third-year grapes should be good enough to try making some wine, but true wine production comes in year four or five.
In the fourth or fifth year, the grapes should be ready. According to the Extension, it's not a good idea to judge maturty of the vine by color of the grape since grapes will naturally change color before they are fully ripe. Taste is a better way since almost all varieties become sweeter and less acidic as they mature.
Taking a look at the seed color is also a good way since seeds change color from green to brown as the grapes mature.