The Noble Art of Spraying

I hate to spray. I hate to spray. I hate to spray....

A Drop to Cure, an Ounce to Kill: Whoops!

I noticed a powdery mildew outbreak in the Aglianico vines along the shed. I had this coming as the canopy is mismanaged, not allowing good airflow. But, I've learned a few things since last year, when mildew spread across half of the vineyard and I found it difficult to control (and lost 1/2 of the Petit Sirah and 1/2 of the Grenache crops). There's miracle, organic, JMS Stylet oil that arrests mildew outbreaks. The recommended dilution rate with water is 1% to 2%, so I remembered from elementary school there are 16 oz to a pint, 32 oz to a half gallon and 64 ounces to a gallon, right?* So if there are 64 oz to a gallon then I should blend in 6.4 oz of stylet oil per gallon, right? Wrong! The correct amount is .6 oz. What was I thinking?! Alas, I overdosed the vines. Fortunately, light was running out that evening, and I only attacked the worst spots, and I got the dosage correct for the rest of the block. The two pictures above show dead leaves and shriveled grapes as a result of my mistake. I've heard that vines are tough characters, so I think these guys may come back with time. The picture below shows healthyAglianico vines I sprayed with the correct dosage. I wonder when they're going to need some water?

*(Wrong! 128 ounces to a gallon! So the correct dilution is 1.2 oz per gallon + / -)

If It's Thursday We Must Be Spraying

Frank,

Looking forward to seeing you on Thursday. There's been a "cold wave" in these parts with fog each morning and moisture on the vines. The afternoons have been warming up over 70 degrees, and the mildew index is at 100. It's been two weeks since the last spraying, and we've been busy removing excess laterals from the fruiting area. The vines will be ready for another spraying on Thursday.

Based on our experience last time, here’s what I suggest:

Start at the “back gate” (off of Merlot Mike's road) at the top of the hill (by the shed). I’ll leave the back gate open and put some 2 X 4’s up there to make it easy to unload the sprayer from your truck. There’s a hose by the shed you can use for water.

The whole vineyard uses just shy of a full tank of your 32 gallon sprayer. We have 1,150 vines spread out over 2 acres. I suggest “dosage” as if you’re dosing 1.5 acres.

Let’s use Rubigan. (We sprayed 2 weeks ago using Rally.)

FYI, we are battling a mildew infestation on the Aglianico vines – this is the block at the top of the hill around the shed area (flat area at top). I sprayed JMS Organic Stylet oil one week ago. Things seem to be under control. But if you see they are out of control, let me know.

Using your power hose, not sure if it’s possible to control the stream so you get broader leaf coverage, but if so, the foliage is thick, and I hope you can cover it all.

I gave in and watered 3 rows of Tempranillo vines (at the top in a rough area) on Sunday that were beginning to show signs of stress, but other than that, have not watered vines (except for Admire treatment). Let me know what your impression is about signs of stress vines are showing (or not showing) and if there’s a need to water soon. (All that vigorous growth you're seeing is the work of nature and the 15" of rain we had over the winter.)

Please bring invoice for the Admire treatment and Thursday’s spraying. I’ll leave a check with the Queen. Would like you to leave with a check -- it's good for cash flow.

Please pencil us in for July 8th (Thursday) or the 9th. Based on my experience last year (and talking with other vineyard owners), the Aglianico vines will very likely need another spraying.

Call me with any issues or concerns. Thanks for your help, and if it’s possible to enjoy the work (or at least the views), then enjoy. (Be sure and grab a tangelo; they’re delicious!) And watch out for that snake out there among the rocks.

Cheers,
Bluey & Craig

(P.S. Picture is of mildew free Petit Sirah / Durif cluster at foggy dawn. This area was ground zero for the mildew explosion that almost wiped us the Durrif harvest last year. )

What's Best Way to Spray Vineyard on Steep Terrace?

The challenge was how to effectively spray a small vineyard on a steep slope to keep Powdery Mildew at bay. For some locations, there may be ample space during vineyard installation to terrace wide, flat rows between vines so that a tractor or other four wheeled vehicle (such as a Gator) can be loaded with a sprayer and carted between the rows. (Our property is relatively small and so we didn't terrace the land.) A simple backpack sprayer takes approximately two days and is much trouble as the liquid seems to always get clogged, and the spray in uneven. Another possibility was to purchase a motorized backpack sprayer. This would work, providing a good mist on the vines, but is heavy to carry around. Last year, Frank Bons of Sunfresh Vineyards, who operates a vineyard management company in San Diego County, sprayed the vineyard with a long hose (approximately 300 feet) connected to a large tank on his truck, first stationing the truck at the bottom of the vineyard, then driving by paved road to the back of the property. This operation took another person to manage the hose. Not all vines were reached, and a couple of sections needed to be done with a backpack sprayer. Says Frank, when it comes to spraying, "I don't like your vineyard."

As the Blue-Merle is a difficult vineyard to spray, careful attention is paid to monitoring the mildew index using the University of California, Davis system to make sure spraying is done only when absolutely necessary. Secondly, Frank suggested using a spray such as Rubigan which is effective for 14 - 21 days, depending on the weather. Frank came up with an approach that worked. He brought a 30 gallon pump on wheels to the property, hauling it to the top of the hill, connected to his 300 foot hose. (Next time, remember to drive the pump to the back gate, and lower it using 2 X 4's.) From there, he marched up and down the rows, moving the pump down the hill and across the property as required. The actual spraying operation took less than one hour. Strong pressure from the hose meant he only had to spray one side of each row.

We used 2 oz of Gowan Rubigan (Fenarimol). According to the label, the recommended dosage for wine grapes is 2 - 4 ounces per acre. We have approximately 2 acres of vines and thought we would recharge the 30 gallon sprayer once and so mixed 2 oz. of Rubigan into the machine. It ends up that we used slightly less than 30 gallons (there are approximately 1,150 vines on the property). As this was the first spraying of the season and there was no sign of mildew, Frank thinks a light spraying may have been better. Meantime, we'll continue to monitor the temperatures to keep track of the mildew pressure, preparing for another spraying later this month, using a different spray to avoid resistance buildup.

(Picture above shows grapes infected with Powdery Mildew in early June last year.)

Cancer Discovered In The Vineyard: Powdery Mildew

This is not funny. Really. It's as bad as the consequences of unsafe sex. There's a cancer in the vineyard. And it was as easy to prevent as eating broccoli, brushing a dog's teeth or using a condom.

Was it a result of playing golf on Sunday instead of vineyarding? Was it the revenge of the Three Priests for skipping Church? Did three weeks of unseasonably cool weather, thick fog and drizzle create ideal conditions for it?

There are simple rules in this life: eat your vegetables; check the dog's toes for foxtails; spray your vineyard. Two out of three ain't good enough.

At daybreak Monday Bluey & I went to the lower part of the vineyard where I hadn't been for a while and noticed a bunch of Petit Sirah with white frosting. I cut it off. Then noticed it on another bunch. Mission control, we have a problem: Powdery Mildew.

My experiment in not spraying the vineyard has been terminated with extreme prejudice.

The temperature stayed below 70 degrees today so the infestation did not spread, much. I should have been out in the vineyard holding hands this evening with my sweetheart watching the midsommar sunset and the full-moon rise but instead I was rushing to cut leaves to open up the canopy and scrambling to the top of the hill to fill a backpack sprayer with 4-gallons of water and X-amount of wettable sulphur. The directions said to apply 2 lbs. - 10 lbs. per acre of grapes and we have two acres planted but it doesn't say a thing about how many grams of sulphur to add per liter of water or how many ounces per gallon. So I took my best guess and stirred in the brown powder which disolved nicely in the water and put the sprayer on my back and pumped the handle to build pressure and nothing came out. What next? Momentarily deflated, but not defeated, I sent out an SOS to Coyote Karen to borrow her sprayer and I suggested to the Queen that we call Fidel to help us spray and she started singing her song:

That Fidel I am

That Fidel I am

I do not like that Fidel I am

And the Kabuki play continued about how it's her vineyard and if I think for a minute I have anything to do with it or if it's half-mine then she's leaving or "you should go to China" and she's carrying on about Fidel this (it's his fault the valves are leaking!) and Fidel that (he owes me $2,000 for the work he didn't do!) while the Man in the Moon is coming up and Bluey (bless his heart a dog without a tail) puts his stub between his legs and finds a corner to ride out the storm. This is why hurricanes have female names. Peace is restored when I lie that it's 100% her vineyard, pour her a glass of wine (instead of cutting her off) and promise not to call Fidel, that rascal.

The good news is that the mildew is located in the lower part of the vineyard and we can still save most of the Tempranillo, all of the Zinfandel and all of the Grenache. I have tasted award winning Tempranillo wine made from 3-year old San Diego vines and our vines are ready and willing to give us grape. Philosophically, my wanting to save the grapes is a good thing but if I loose them then I should just give them up because it's just a possession and possessions are temporary and in the end we're just ashes and the vines wither. I'm a mother with a baby inside and despite what the queen says it's my vineyard too and I'm fearful of a miscarriage and so I'm fighting.

Questions: If a bunch of grapes have a little bit of Powdery Mildew can they be saved? How much wettable sulphur powder should I add per gallon?

Spraying & Mildew Control

One of our vineyard consultants -- who will remain nameless today-- believes spraying for mildew where we live may not be necessary very often because we have wide spacing between our rows and good wind flow. Our neighbor (Sunrise Vineyards) has the vines really packed in, and sprays quite often. On the other hand, our other neighbor at Coyote Oaks with 3 year old vines (who uses this same consultant) has never sprayed. Neither have we.

Our friend Gerry -- who grew the excellent Petit Verdot we have in the barrel -- operates a weather station and sends out weekly mildew reports. I had to ask him, in a polite way, is our consultant nuts? Here's Gerry's answer:

"Hi Craig, [the consultant] is not nuts but he does not have all the technical facts about mildew. It depends on grape variety , air flow, temperature, and moisture at the start of the season.. but I use the Davis system (used to be a secret). Some folks will make a big deal of the moisture being important but that is only the thing that gets the mildew started in your vineyard. Once it exists even in a small area it exists and then you have to proceed with protecting your vineyard from getting a major infestation developing. I just assume at the start of the season that I already have some mildew (it stays in the vineyard over the winter by the way). So I am in protective mode from day one. Thus It really depends on temperature and time, Mildew likes its temperature between 70 and 85 deg F. (just like us human beings). I would be happy to describe it to you in person or over the phone. It is simple to do if you have a recording weather station which I have.

The simple version is: 1. do your first spray using Thiolox when the buds just appear... maybe 1" long. The rest of the sprayings depend on your grape variety and the calculated risk level that develops after your first spraying.

2. Each day you have temperature between 70deg and 85deb for 6 continuous hours you add 20 to the risk level. ( If it goes above 85deg for 45 minutes that breaks the cycle and you subtract 10 from the risk level. If it goes above 95 for 15 minutes you get to subtract 10 from the risk level for that day. (That is why the Temecula folks don't worry much about mildew... because it is very hot during their season.

3. the risk value you compute never goes above 100 or below 0. A mild level is 30 or below. 60 is very high 100 is as high as the system will compute it.

4. The day you spray puts the risk level down to zero and you start over. The interval between sprayings depends on the material you spray with. If that first spraying was Thiolox (micronized sulphur) and the risk level goes up to around 40 to 60 or above you only get to wait 7 days til the next spraying..... so you see it depends on the type of spray. I use Thiolox for the first 2 or 3 sprays (or til verasion starts)... I am now using Rally and Pristine... you have to alternate the types of spray unless you are using sulphur which does not need to be alternated with anything except you do not to want to use sulphur near harvest (your wine is affected by it negatively) This is simpler than it seems to be if you can make a good stab at the risk level. If you do not do that just read the label on the material and it will tell you the interval days/weeks...sort of and just do what the label says forget the fancy risk level....you will probably just add one or 2 sprayings to your vineyard for the year. I usually spray about 10 times per year. Gerry."