These past few weeks we have been closely monitoring the rising sugar levels in the grapes in the build up to harvest. To help the vines ripen the fruit, we have opened up the canopy so that the bunches are exposed to sunlight. Reducing the amount of foliage on the vine also helps the vine concentrate its energy into the grapes, however the leaves are essential for capturing the sunlight, so a decent amount needs to remain. We have also been spraying biological control agent, to help protect against bunch rot.
However what is really essential is that the sun shines on the vine, to allow the vine to photosynthesise and in turn ripen the grapes. We do have a sunny weekend forecasted, but wind and rain for next week.. not good!
We will take the sugar levels again today using the refractometer. This measures the degree to which the light changes direction, called the angle of refraction due to the density of the juice (which is changed by the sugar levels). Each degree equates to one gram of sugar per one hundred grams of grape juice.
You need to take randomized samples of berries from across the vineyard, because the vines all ripen slightly differently, depending partly on whereabouts they are in the vineyard. You collect the grapes in a plastic bag and fully squash all them all, releasing the juice. You then make sure that the juice has all been mixed up, take the pipette and drop some juice on the the refractometer. You need to take three samples and then you use the average.
So far, the Chardonnay is ripening the slowest, followed by the Pinot Noir, and then Pinot Gris & Meunier, both of which taste pretty good! According to Juniper they taste peachy!
I once had an amazing work experience job in Napa Valley, taking sugar readings across different vineyards. Whereas in England you are dodging rain, wind and earwigs (they seem to like to hang out in the bunches). In Napa, I was trying not to stand on rattle snakes and get sun stroke. In England, we are desperate for the sun to ripen the grapes, in Napa they are waiting for the perfect moment where the sugar peaks, but the acid doesn't drop too much. When it gets too hot, the vines also shut down, so both environments can be challenging. I'll take earwigs over rattle snakes, but Napa sun over this October Sussex weather.
Watch this space...