So, What’s Happening in The Orchard?
Wow! It is already August and apple season is just around the corner. But before we here at Kimmel Orchard can really start to think about picking apples, we need to harvest our grape crop. And what a crop it is. One of the best in recent years. We just finished harvesting Edelweiss and will start harvesting LaCrosse next week. Soon to follow will be another white grape—Vignoles—and then on to our red varieties. These include DeChaunac, Chambourcin and Frontenac.
So, how do we know when the grapes are ready to harvest? Harvest is based on the sugar content of the grape berry. The greater the sugar content of the grape berry, the riper the grape. We use an instrument called a refractometer to determine the Degrees Brix of the grape juice. One degree Brix is 1 gram of sucrose in 100 grams of solution (juice). The higher the Brix level, the greater the sugar content of the berry.
Generally speaking, we want the highest Brix level we can get within reason. The longer the grape hangs on the vine, the greater the Degrees Brix becomes. As the grape hangs longer on the vine, you increase your opportunity for crop loss from insects, disease, birds and weather. To reduce the risk, we try to harvest somewhere in the range of 21 to 24 Degrees Brix. There is one exception to this rule of thumb and that is Edelweiss. Edelweiss is harvested at around 14 Degrees Brix which is very early in the ripening process.
Today, I pulled a random sample of 100 LaCrosse grape berries. The juice tested at 19 Degrees Brix. Several factors affect the Degrees Brix level on any given day. A berry sample pulled on a cloudy day will have a lower Brix reading than one pulled on a sunny day. Recent rain can also reduce the Degrees Brix and may have an effect for 2-3 days depending on the amount of precipitation that was received. The ideal sampling conditions are a sunny day as the grapes begin to warm up at about mid-morning.
Another sampling that we take prior to grape harvest is used to estimate the crop load of the vines—how many pounds of grapes we are producing. To estimate yield, we randomly select 10 vines of the variety being tested and weigh the grapes harvested from each plant. We then calculate the average yield per plant and multiply that by the number of plants of that variety. The final number gives us a very close approximation of the pounds we will harvest. We can then use the pounds of grapes we harvest to calculate how much grape juice will be produced. Approximately 12 pounds of grapes will yield 1 gallon of juice, so if we harvest 4,000 pounds we will get 333 gallons of juice or 1,665 bottles of wine. Knowing these numbers are very important to us in determining the direction we will go with our harvest.
Our next workshop—Growing Fruit Trees in Nebraska—is quickly approaching and there is still time to get registered. Now is the time to start planning and getting ready, as preparation is the key to success; and the first of the catalogs for next year’s orders will be arriving soon. The details are as follows:
Saturday, August 25, 2018
9:00 AM to 2:00 PM
Kimmel Orchard and Vineyard
5995 G Road
Nebraska City, NE
$35.00 – includes lunch & breaks
To register or questions, contact Kimmel Orchard & Vineyard at 402-873-5293
Once again, I would also like to take this opportunity to invite everyone out to visit Kimmel Orchard & Vineyard. We strive to make it a new experience each time you visit us. We guarantee that there is always something new to learn or see at Kimmel Orchard & Vineyard.
Vaughn Hammond –Orchard Operations and Education Team Leader
To stay on top of everything going on at Kimmel Orchard & Vineyard, follow us on Facebook, Instagram and Snapchat or visit us at www.kimmelorchard.org.