January 5th, 2022
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Winegrape Nutrition
Understand Your Goals to Understand Your Fertilizer Needs By FRED STRAUSS | CCA, Doctor Sustainable, LLC
goals. Let’s address how to build the right fertilizer program for your needs.
Know Your Needs
You must know the nutritional needs of your grapes to know how much to apply. Conventional wisdom is winegrapes use 9 lbs. of nitrogen, 3 lbs. of phosphorus and 13 lbs of potassium for each ton harvested. Again, there are slight differences from white or red and even varieties.
You must know the nutritional needs of your grapes to know how much to apply. Conventional wisdom is winegrapes use 9 pounds of nitrogen, 3 pounds of phosphorus and 13 pounds of potassium for each ton harvested (photo by Marni Katz.)
W
inegrape growers are a very diverse group. Some growers grow for volume or high yield, not necessarily high quality. Some growers grow for high quality while yield is secondary. There are, of course, 8
Progressive Crop Consultant
many growers in between. Maybe you are a conventional grower, or a sustainable grower, or an organic grower, or a biodynamic grower, or, well, you get my point. In order to understand your fertilizer needs, you must understand your November / December 2021
If you have established grapes, you must determine where you are at with the condition of your soil and quality of your water. Soil sampling is a yearly function as well as a water sample, no matter the source of the water. The amount of nutrients, or lack of, in the soil will help you realize what you need to do. Water quality needs to be known as well as the amount of nutrients in the water. Well water can contain some levels of nitrogen and other needed nutrients, but also excess salts and boron. The pH level of your water can affect the availability of nutrients in the soil as well as the fertilizers you apply. Since many fertilizers are applied through irrigation systems, pH becomes a big deal and causes fertilizer to separate in the system. A CCA can help you get through these technical issues. How much fertilizer do I apply, what kind, when, and will it go through my system? A good advisor will also do in-season leaf samples to see where you are with the health of your grapes. These samples are done at specific stages of growth and even