Looking for dry farming wine grapes tips and info.

[SLOweather]

As I posted in my intro, I'm interested in dry farming an acre or 2 of zin near the Central California Coast.

I understand from the local extension person that it's done by a couple of wineries up in northern San Luis Obispo County, but I haven't been able to make that field trip as yet.

So has anyone here dry farmed wine grapes? Any tips, or information you can share?

 

[grapeman]

I dry farm my acres of grapes, but it really isn't the same as it would be, with me being in the northeast. We typically get 30+ inches of rainfall so I just don't have a need to irrigate. Hopefully you can get somebody to chime in. You can try going to the WinePress.US site and go to their forum. A lot of the guys on that one are in California and probably can help a lot more.

 

[SLOweather]

I dry farm my acres of grapes, but it really isn't the same as it would be, with me being in the northeast. We typically get 30+ inches of rainfall so I just don't have a need to irrigate. Hopefully you can get somebody to chime in. You can try going to the WinePress.US site and go to their forum. A lot of the guys on that one are in California and probably can help a lot more.

Thanks! I'm there now, waiting to get validated...

 

[grapeman]

Be sure to check in here when you get wine making questions, etc. The guys here are the friendliest around, but we don't mind telling you of other places that might help you where we can't do as well as we would like.

 

[vinharold]

Hi,
Dry-framed is vineyards are all I make wine from and I am curious to know more about your project?

 

[SLOweather]

Hi,
Dry-framed is vineyards are all I make wine from and I am curious to know more about your project?

Well, calling it a project is a bit premature. At this point, it's more of an idea becoming a concept on its way to growing into a project.

We live in the Irish Hills/Prefumo Canyon area of San Luis Obispo, CA, and can see the Edna Valley vineyards 5 miles away from our back deck. In the last couple of years we've gotten more interested in the local wine scene, and recently we've become friends with a farmer/wine maker/orchardist whose farm is about 12 miles away in another canyon closer to the ocean.

A couple of weeks ago, we had them over for a little BBQ and wine down in our woods (home of the cabin in my avatar) and he mentioned that our back hill might be good for dry-farmed zin. It's a SSW facing slope, and there's maybe 1-1.25 acres available for planting. Dry-farmed is preferred due to our limited water supply. (I run our 58 member water company, and measure the wells every week, as well as the rainfall, so I know the water situation. I also have popular local weather site www.SLOweather.com and have 10 years of good weather data from our property.)

Other wineries in the SLO and Paso Robles area commercially dry-farm zin, so I know it can be done. I'm in the study/learning phase to see if this is something we can and want to do. A a part of the early study, I planted out a half dozen Vitis Californica Roger's Red along the downhill fence line to see how they do while I figure the rest out.

 

[theprodigy]

I know it's being done in California with Zin. Is there any reason if you are going to dry farm, Zin is the best choice?

 

[Randoneur]

I'm thinking it does not matter as much if you are doing Zin vs. something else, but the rootstock is the most important decision for your micro climate and water availability.

 

[AlFulchino]

agreed regarding the rootstock......do your homework and talk to the local growers....good luck on this!

 

[theprodigy]

In California how much could you save a year (per acre) by dry farming?

 

[vinharold]

Savings

The only "savings" that I can think of for dry-farming fruit would be the savings associated with not installing drip irrigation for vineyard establishment and the savings of a vineyard that has a longer economically viable life span.
On the right site these are real savings. In addition dry-farmed grapes of high quality can fetch a higher price than irrigated grapes and this value gap is bound to grow if dry-farmed gains more traction as a marketing tool. Regulatory battles to follow.

 

[SLOweather]

In California how much could you save a year (per acre) by dry farming?

Well, using numbers from the UC Extension publication 2005 Sample Costs To Establish and Produce Wine Grapes, p. 14...

An acre of grapes uses 21 acre-inches of water per year. That's 1.75 acre-feet per year, or 76,230 cubic feet, or 570,200 gallons per year.

If I read the paper correctly, that's for 760 vines per acre, or 750 gallons per vine per year. If I back out 3 months (90 days) of rainy season, that's 275 days of watering, or an average of 2.7 gallons per vine per day. As a back-of-the-envelope calculation, that seems reasonable, considering that most of the time irrigation would not every day.

If we planted 3/4 acre of grapes, that would be about 570 vines, or 1.31 acre/feet per year.

We have an allocation from our water company, imposed by the county as a part of a couple of EIRs, of 1.22 acre feet per year. This ensures the long-term stability of our underground water source.

In 2011, my wife and I used 14,592 cubic feet of water, or 0.33 acre-feet. That was a wet year, so assume our dry year consumption is 0.50 AF. (This year is shaping up to be a dry one.) All of our landscaping is unirrigated California native plants. All we water is about 100 square feet of grass for the dogs, some raised vegetable beds, and a couple dozen potted roses.

So, 1.22 AFY allocation - 0.50 AFY use leaves 0.72 AFY for other uses.

Monetarily, if we could get 1.31 AFY (57,064 cubic feet) from the water company, that would cost over $1,000 per year.

Drilling our own well is not an option. It's partly for the cost, but mainly because one of the water company wells is already on our land. Drilling another well doesn't get more water any more than putting a second straw in a Pepsi gets more soda. It just drains the glass faster.

Dry farmed grapes would seem to be the way to go. As it is, we could come close to our allocation for a year or 2 just to get the vines established...

 

[grapeman]

Does it ever rain there? If it does, you need to figure that amount of water into the equation.

If you have a 55 gallon drum filling slowly and you put one straw in it and start drinking, will it ever go dry? Probably not and you could have you friend drinking out of a second or even more straws without depleting the barrel. Same thing for a water well. If your well never pumps dry, you likely could handle another on the aquifer alright. My Town used to have 3 -12 inch wells pumping the water for the whole town on the same aquifer as I am on. Yes we likely have more water than there, but I think you could explore the option.

 

[SLOweather]

Yup. Our average is about 23" per precip year, which runs from July 1-June 30. Last year our weather station received about 36", this year is looking much drier.

And all of that was figured into the water supply calcs by the hydrogeologists for 2 different EIRs for 2 tracts in our 58 lot mutual water company. I believe they were figuring on safe annual yield for a 7 year drought.

As the water company president and operator, I pay really close attention to rain and its impact on the wells. Among other things, I read all of the production well water and electric meters monthly, and all the customer meters bimonthly.

We have 6 hard rock wells, all in different formations but 2. Hard rock formations do not have the porosity and storage volume of gravel or sand aquifers.

And, I measure depth to water in all the wells weekly, as well record the previous 7 day total rain. In order to ensure accuracy, besides the weather station tipping bucket gauge, I use a 4" Stratus and 8" NWS Standard Gauge for comparison.

In the data, one can see the direct impact that the rains have on well levels after the ground is saturated. A week ago we had ~4.5" in 2 equal storms. The first one saturated the ground nicely, and then the second one mostly ran off. wells that were dropping a few tenths of a foot per week came up > a foot.

We've had one well go dry a couple of times, which is what prompted all of the measuring and calculating. Its production is off severely from what was calculated back in the 90s. I think something shifted underground during the Dec 1993 magnitude 6.5 San Simeon Earthquake. That was quite a roller here, the biggest quake I've felt by far in 39 years of living here.

By my calcs, that well has lost 75% of what they thought it could produce in the mid 90s.

Knowing everything I know about the water company's situation, I don't dispute that the water is probably there. However, we have to all live within our shared resource and allocation, the penalty for which exceeding is quite severe.

 

[grapeman]

I find all that quite interesting - and I am glad we don't have those problems in the Northeast. I think a lot of the water need there must be your temperatures and relative humidity levels. We only get about 10 inches more than you do there per year and rarely does it ever get dry enough to stress the vines. But then again our temps are much lower on average. I will be following your posts with keen interest.

 

[SLOweather]

In looking at your average monthly precip, you also receive at least 1.5" almost every month, the bulk of it during the summer growing months:

http://www.weather.com/weather/wxclimatology/monthly/graph/12962

OTOH, our rain comes mainly in the winter, almost a direct inverse of yours, with dry summers:

http://www.weather.com/weather/wxclimatology/monthly/graph/93401

And, you can see from the graph why our "rain year" is considered to be from July 1 - June 30. This is the average for the city. Our location adjacent to the Irish Hills receives a little more rain from most storms due to orographic enhancement.

Your temps are higher in the summer, and presumably more humid; and colder in the winter. We are tempered by proximity to the Pacific Ocean, so both our summers and winters are milder:

Morrisonville:

San Luis Obispo:

Just 30 miles north, on the other side of the Coast Range, the Paso Robles wine region is hotter in the summer, colder in the winter, and receives less precip that we do. There are a few wineries up there successfully dry farming zin, and probably other grapes.

 

[grapeman]

I love seeing contrasts like these in different regions of the same country. It reinforces the fact that when we make recommendations, it is always handy to know where the poster is located. We may be in the same country, but our weather varies a lot. Thanks for the comparative graphs. You certainly do have a dry summer there! No wonder there are water problems. Thanks

 

[AlFulchino]

but what is left unsaid here is that the lack or rain is a HUGE HUGE blessing in terms of not spreading fungal disease

have you considered large holding tanks for water and use it for moderate irrigation if and when needed?