Fighting Frost, Protecting Profits

The late spring frosts that periodically strike the North Coast can have a big impact at harvest time. When the night skies are clear, watch out! Last year's frost hit the industry hard, and no one can predict what will happen season to season. If frost bites your maturing canes and buds, new growth will be badly damaged, stunting grape production.

When frost threatens, the most efficient and cost effective weapon you have in your battle against cold is your irrigation system. Right now is the time to put your defense in place. If you haven't yet, get out in the field and make sure your irrigation system is in excellent operating condition. As cold as it was in the last week, we'll bet you're going to need it. Too understand more about how to measure critical temperatures in your vineyard, download instructions to construct a US Weather Service-approved thermometer shelter.
It's a PDF, size 64k; Adobe Acrobat Reader required.

Releasing the Warmth of Water

There are two ways that irrigating on cold nights acts to protect fall's harvest. First, for bud protection, you irrigate overhead to cover the bud with ice. At 32°, as water turns to ice, it releases 144 BTUs of heat, keeping those buds snug until the morning sun comes to their rescue.

Secondly, when air is humid, it's denser. Denser air is a better insulator and it actively holds in the earth's daytime heat. As nighttime temperatures drop, the water you're spraying into the air condenses, releasing warmth into the under-vine environment. For more understanding of when to turn on your sprinklers, download Rainbow's frost protection information sheet.
It's a PDF, size 40k; Adobe Acrobat Reader required.

For another interesting article on frost protection, click on the link below:
CSU-Fresno research report on "Microsprayer Frost Protection in Vineyards"

Before you select any method for frost protection, contact Rainbow Ag's irrigation design engineer, Steve Shepard. Steve will share his 15-year North Coast experience with you. Read Steve's bio below.

Preseason Disc Sale! Save up to $2000! Limited to stock on hand! See details on our website.

Overstock Sale on John Deere New Vineyard Tractors Gondola Rental Returns 4 TO CHOOSE FROM List Price $32,000 Your Price $22,300* John Deere 5320 4WD 55 PTO HP Great Financing Options! 12-month finance waiver OR 3.5% variable-rate financing up to 60 months *After $600 cash discount; subject to John Deere financing approval. See details on our website. Come in to Rainbow or call: Jim Munson, Lake/Northern Mendocino (707) 468-6549 (pager) munsonjim@netscape.net Bob Mitrovich, Napa/Sonoma/Mendocino (707) 316-2108 (pager) BobMitro@aol.com Jerry Smith, Napa/Sonoma (707) 324-1940 (pager) jvsmithbow@aol.com

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Take Notice! Important Upcoming Event Irrigation Strategies & Quality Grapes March 21, 2002, 7:30 to 9:00 p.m. The Sonoma County Vineyard Technical Group has invited area viticultural experts to discuss how irrigation scheduling can maximize wine grape quality. Arrive at 6:30 pm, and mix with others during a one-hour enjoy wine social. Free. Where: Kendall-Jackson Wine Center, 5007 Fulton Road, Santa Rosa For information about the program or membership, call (707) 462-6624.

And the Winner Is... Joe Battaglini Battaglini Estate Winery, Santa Rosa. As you can see, Joe is a happy guy. While attending The Wine Grape Symposium in Sacramento at the end of January, Joe stopped by Rainbow Ag's booth and signed up for our chainsaw drawing. That's Rainbow's Husquavarna chainsaw Joe's holding. After winning, Joe said that his old chainsaw had recently bit the dust, so our drawing was kind of timely for him. Conferences are always a good thing for people who want to stay on top of their game in our industry, and Joe's skill as a winemaker is becoming well-known, but there's always something to learn (and to win!) at these important events. (P.S. Next year, make sure you don't miss Rainbow's booth. You just never know what we might have in store for you!)