Last week we reported expecting budbreak in our vineyard to happen around St. Patricks Day, March 17.
Today we saw the first signs of leaves breaking out of their protective enclosures. Pretty close, eh?
Vintage 2013 has started!

We bottled the very first batch of Cabernet Sauvignon from our vineyard. Harvested on October 10, 2010, so appropriately named 10-10-10. This wine was hand harvested, hand destemmed and manually pressed. Too much work in hindsight.
We know better now and use a motorized crusher/destemmer and basket press.
We added some oak cubes to increase complexity.
The result is a smooth, fruit forward dense wine. As it matures, the primary aroma's of cherry and blackcurrant will slowly get replaced by an even nicer nice bouquet. That's the charm of wines that get aged for at least 3 years.

Some winemaker specs:
pH 3.8
TA (acidity) 6.8 gr/l
Alc 12%

We changed the clock forward to daylight saving time, and are getting close to St. Patrick's Day, celebrated on March 17. This is the time where we see the first vines spring back to life and some Temecula vineyards already reported  budbreak. As usual, the white varietals are the first to show their first leaves.

Our vines have decided to stay dormant a little longer. Last weekend there was still no sign of budbreak in our vineyard, but we are getting close. Meanwhile, we have applied some fertilization as the Temecula soil is nitrogen deficient. When our vines wake up, they'll have sufficient nutrients and energy for the new vintage.

The new Google Trends tool, released in October last year, provides interesting patterns and shifts in consumer wine interest. I entered 4 popular red and white wine varietals, and got below trend results for the United States.

No surprise: Google searches for all wines peak annually in December. White wines show increased interest in Summer as well.
General interest in red wine was lower during the peak of the financial crisis. White wine was hardly affected.

Cabernet Sauvignon wine is back in favor with the American public. Merlot however shows a steady decline in interest, and is now overtaken by Pinot Noir and Cabernet Sauvignon. Effect of the Sideways movie (2004) worn off?
Most sought after wine on the Internet is Pinot Noir.
Zinfandel fans seem the most loyal, as interest since 2004 has remained stable.

For the white varietals, Chardonnay is unbeaten as the USA white wine of choice, but interest in other varietals, like Riesling and Sauvignon Blanc is growing.

The Vinduino project goal is to provide an accessible measurement tool for smart irrigation management. Although the Vinduino soil moisture measurement project was originally developed for saving the irrigation cost of our vineyard, it can equally well be used for other agricultural applications, a school science project, or even to reduce the water consumption of sprinklers in your own backyard. While this is a "technical" project, we have tried to keep it low cost, accessible, and easy to reproduce.

The updated version 3.0 of the Vinduino code for the Arduino open source micro controller board is now available for free download, thanks to contributions from Theodore H. Kaskalis. Technology Management Department, University of Macedonia, Greece.
Theodore co-authored a paper about smart digital farming: An Embedded System for Smart Vineyard Agriculture

Vinduino 3.0 improvements include:

• streamlined and corrected code

• sensor calibration equation
• median noise filter instead of averaging filter

Download the Vinduino code here (5kb) ("save link as")

For an overview of all Vinduino project related postings click here

This is free and unencumbered software released into the public domain. Anyone is free to copy, modify, publish, use, compile, sell, or distribute this software, either in source code form or as a compiled binary, for any purpose, commercial or non-commercial, and by any means. In jurisdictions that recognize copyright laws, the author or authors of this software dedicate any and all copyright interest in the software to the public domain. We make this dedication for the benefit of the public at large and to the detriment of our heirs and successors. We intend this dedication to be an overt act of relinquishment in perpetuity of all present and future rights to this software under copyright law.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

We're back from the holidays and New Year's break. There is a lot of activity in Temecula wine country at the start of the season. Time to prune the vines. Our vines are cordon trained, the old wood (two arms/cordons) remains attached to the support wire. We typically leave 2 buds per spur position. Each bud ideally grows into a new fruitful cane, producing 2 grape clusters.
This is also the time to assess the health of the vines. Usually there is a number of vines that did not make it through the winter, and we need to plan for removal and replacement.

This year we plan to propagate vines by taking 12" cuttings- leftovers from pruning- and grow new plants from these. Grape Phylloxera is not of significance here, so we can plant our new vines without special rootstock this Summer.

Parts of the vineyard show multiple mounds of freshly dug soil dug by pocket gophers. They can do a lot of damage by feeding on the grape vine roots. To keep the gopher population controlled, we had traps placed this week. The remainder of the season, we rely on the local predators- mainly barn owls, coyotes, and snakes- to keep a natural balance.

The last day of the year started with a nice frosting over the fallen leaves. After sunrise temperatures went up pretty rapidly, and today turned out to be another typical "blue sky" California day.

This weekend we did a vertical wine tasting with a couple of our good friends, comparing our 2010, 2011, and our young 2012 Cabernet wines. It must be said, aging wine really brings it to its full potential. While the young wine displays it's fruity notes, the matured wine's bouquet really adds a different dimension. And -after 3 years- it has still room to develop further.
Nothing earth shaking, but still nice to actually experience the development of wine.

In Temecula, pruning of some vineyards has already started. First sign of the new season, and we are looking forward to it.

Happy New Year everybody!!

Merry Christmas! The new version of the Vinduino code for the Arduino open source micro controller board is now available for free download.

Improvements include:

• moisture percentage indication 1% - 100%
• sensor calibration equation
• wider sensor resistance range
• Support for the "Ohm" character

Download code here (5kb) ("save link as")

For an overview of all Vinduino project related postings click here

This is free and unencumbered software released into the public domain. Anyone is free to copy, modify, publish, use, compile, sell, or distribute this software, either in source code form or as a compiled binary, for any purpose, commercial or non-commercial, and by any means. In jurisdictions that recognize copyright laws, the author or authors of this software dedicate any and all copyright interest in the software to the public domain. We make this dedication for the benefit of the public at large and to the detriment of our heirs and successors. We intend this dedication to be an overt act of relinquishment in perpetuity of all present and future rights to this software under copyright law.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Part of a winemakers' job is to perform frequent chemical analysis to track the development of his/her wines. The most  important properties measured are Brix (sugar content of grapes), SG/specific gravity, acidity, pH, alcohol %, and sulfite level.

Here are some of our analysis results of our Cabernet Sauvignon 2012 grapes from the month before harvest to November, showing how the chemistry changes when grapes transform into young wine.

Harvest
For the decision when to harvest, we follow the development of Brix (sugar content), pH, and TA (acidity).  Picking the grapes at the right moment is important for creating a balanced wine

Fermentation
As soon as yeast is added to the grape must for primary fermentation, sugar is converted into alcohol and CO2. The Brix line went down, and the alcohol level went up to 13%. When fermentation is done, we stop measuring Brix/SG.

Malolactic fermentation (MLF)
After completion of the primary fermentation, we added a malolactic bacteria culture that converts tart-tasting malic acid (think green apples), to softer-tasting lactic acid. This process increases the pH and lowers the acidity. We had to make a small pH adjustment, allowing for a lower sulfite level to protect the wine against spoilage and oxidation.

While wine chemistry can be a lot of fun, frequent tasting remains the most important and rewarding aspect of wine making!

The Arduino micro controller board used in our Vinduino project measures the electrical AC resistance of gypsum soil moisture sensors. As we are interested in the actual soil moisture in our vineyard, we wanted the Vinduino reader to display soil moisture as well as sensor resistance. First step to get there is calibration of the sensors to find the relation between resistance and moisture level.

We measured the weight and electrical resistance of 6 sensors, starting with sensors that were fully soaked and saturated with water, and keep repeating the measurements until the sensors were completely dry. The weight difference between fully saturated and completely dry sensors was used as calibration point for 100% and 0% moisture respectively. The idea behind this is that the soil sensor would reach moisture equilibrium with the surrounding soil, and moisture in the sensor is assumed to be the same as the surrounding soil moisture level.

The measurement results are shown in below scatter chart.
The trend line (continuous line) was used to convert measured electrical resistance into moisture level  percentage. For sensor 3 and sensor 6 we found that trapped air from casting the gypsum was the probable cause for measurement differences between 40-15% moisture. Apart from that, all 6 measured sensors followed the same moisture/resistance curve pretty close. We have not made measurements at different temperatures to check temperature dependency.

Conversion equations (Excel) found for this particular type of sensor are:
Resistance=331.55*POWER(Moisture,-1.695)
Moisture=POWER((Resistance/331.55),(1/-1.695))

The Arduino Power function was not usable for moisture levels between 100% and 50% with above formula.
The solution is a workaround using below program line, which has the same result as above equation, but with much better output granularity:
moisture_pct = pow(float(Rsense2/31.65),float (1/-1.695))*400;

Measurement data tables (Excel file) can be downloaded from this link. Sensor Calibration

For an overview of all Vinduino project related postings click here