A couple days ago, a friend asked me: “When do you pick grapes for wine?” After I gave a very quick answer – “later on in September” – I began thinking about all the different things that are taken into consideration before harvesting any crop. Then I remembered a minister at a recent funeral saying: “There is a time to plant and a time to pluck-up!” Then I remembered a story once told at a funeral explaining the little “dash” on a tombstone between the birth and death date engraved there. It’s what you do between when you are born and when you die that is important. It’s the same with a crop of anything. How you live or how a crop is looked after is what is remembered. 

When I was a kid three quarters of a century ago, farmers that made “patriotic hay” cut before the first of July were considered better farmers than those who made “orange hay” that was cut after the twelfth of July. Farmers who cut their hay early in June had better milk production than all the rest, and they also took off a very good second cut of hay. The later that hay is cut, the higher the non-digestible fiber in the hay, and cattle take longer to digest that hay and give less milk.

Now, farmers watch non-structured carbohydrates, available protein, and acid detergent fibre in the hay. Many farmers also watch the sugar content in the hay and corn silage that they make the ration with for cattle, and in the grape juice that they are making wine from. They use a small handheld refractometer to measure the sugar content in a drop of juice squeezed from the crop being harvested, (haylage, corn silage, or grapes). Sugars are very important to the digestibility of a cow’s ration and to how the grape juice ferments when making wine. Sugar content changes from year to year and also can be changed with the calcium content in the soil where the crop grows. Rations fed to cattle can be adjusted by increasing NSC (non-structured carbohydrates), but grape juice for wine increases as the grapes mature, and if they must be picked before the sugar is high enough. This year was very dry in August and grapes grew slower. Now when we are getting lots of rain, the grapes may grow bigger faster than the grape skins can and they may split causing grapes to attract bees and even rot if not harvested when the first split grape is noticed. 

Usually, grassy hay heads out faster than alfalfa or clovers do and hay harvested before it heads out will be much higher in protein and lower in non-digestible fibre for higher milk production, with less expensive grain needed. Grape juice too low in sugars must be supplemented with enough added sugar to make the best wine that is not too dry. I learned many years ago that Italians who make their own wine only use pure cane sugar to make wine. There are many different varieties of grapes that have been developed in different climate zones and mature at different times. 

Wild animals and birds are excellent at determining the correct time to harvest, when the sweet corn is just right or when the grapes are the sweetest. Farmers who grow sweet corn do not plant it near a forest where the wild animals stay. Grape growers use many different scarecrows that look like birds of prey or electronic devices that emit sounds of birds in distress to scare away grape-loving birds. Sometimes birds of prey, like hawks or owls, will spend time in the fall nesting in trees close to a vineyard and deter grape eating birds from hanging around. Birds are quite observant and watch to see if those bird scaring devices are in the same spot too long. Those scarecrows and sound devices must be moved regularly.

The digestibility in grass haylage or hay is higher than in legume haylage or hay harvested at the same stage of maturity. A noted dairy nutritionist once told a group of dairy farmers that the reason that many dairy farmers in the northern part of Quebec had very good milk production was because, “they can’t grow alfalfa that far north and they don’t read a very famous dairy magazine produced in the U.S.,” because it is only printed in English. At that time the U.S.A. thought that a dairy farmer had to grow only pure alfalfa hay. Now most dairy farmers plant a mix of fast recovering grass and legume mix for best hay or haylage, giving three or four cuts of hay each year. 

So, when do the grapes get picked? Watch the lady with the refractometer and watch when the birds start hanging around. You might hear a funny sound in the vineyard like a bird in distress too. There are a lot of things that happen on farms during that dash.