What will you need to join in the fun?
- Garden clippers. If you have a pair, bring them! Gathering Ground has a small supply of clippers that we will lend out as well.
- If you want to purchase some grapes to make your own jams, jellies, juices, vinegars, or wine bring a container to take them home (5 gallon bucket with lid, perhaps).
- A place to stay. Need a recommendation for Island accommodations? Inquire with us.
When is harvest?
La Crescent Grape (the white grape) looks like it will be ready for harvest the first week of October. We have less of this grape planted in the vineyard.
St. Croix (the red grape) is behind schedule. It looks like they may be ready to harvest the last two weeks of October.
We know that it is hard to plan a trip for harvesting if you are not sure when the grapes will be ready! We promise to keep you up-to-date on the state of the grapes. We will be posting updates to Facebook, Instagram and we will send out updates over email. #grapewatch2017
How do we know when grapes are ready to harvest?
This week Tim Lyons and Russell Rolffs tested the brix level in the grapes. Technically, brix measures the amount that light is bent when it passes through a liquid. In grape juice, the sugars, amino acids, vitamins, minerals, etc. cause the light to bend. Thus, the brix level is testing the sugars and nutrients of the grapes. The higher the brix, the more sugars.
Using a simple refractometer and just a few drops of juice from the fruit, Tim and Russell learned the level of brix in each type of grape. Right now, the La Crescent is reading at 12-13, and the St. Croix is only at 8. The ideal brix level for both grapes is about 16-17.
The St. Croix is behind schedule. Likely this is due the cool, rainy summer we have had. To increase their brix level, the grapes need sunlight.
Before the grapes turn color (a process called veraison), grapes are acidic and green-colored due to chlorophyll, which helps the plant process sunlight. When veraison begins, the chlorophyll in the grapes is replaced by anthocyanins for red grapes or carotenoids for white grapes. (These are the same compounds that turn autumn leaves orange and yellow or red and purple). As the grapes turn color, they begin to increase in size and in sugar and nutrient content. Grapes are ready to harvest when they’ve achieved the right balance of sugar and acids.
Alas, there is no perfect formula for predicting when the grapes will be ready to harvest. That is why we will be posting updates via email, Facebook, and Instagram.