How to fertilize grapes?

Question:I just read about a fertilizer called "phostrogen" to fertilize grapes. I was just wondering if anyone knows anything about it and how to use it. Do you use it around the trunk or is it folier?

Answers:
First, you need to know that grapes prefer a soil pH between 5.5 to 6.5 (acidic). At that range, their roots are able to uptake more of the available nutrients in the soil. You can purchase a cheap pH meter from most garden shops or hardware stores. They're NOT the most accurate but they'll give you an approximate range as to where the pH is.

Newly planted vines should not be fertilized because of their tender roots.

Adding compost or manures to vineyard soil enhances soil quality through adding organic matter, improves soil structure, and increases populations of soil microorganisms. These organic fertilizers can reduce or eliminate the need for synthetic nitrogen fertilizers.

Apply 30 pounds of steer manure evenly with an additional 20 pounds of compost around each vine and apply a sufficient amount of water after. This should be done when the buds start to swell in the spring;

However, if you prefer to use synthetic fertilizers,
For 2 and 3 year old vines, apply no more than 1/4 pound of 10-10-10 fertilizer in a circle up to 4 feet away from each vine. In following years when the vines are established, apply about a pound up to 8 feet away from the base if growth was slow or foliage color poor the previous season. Fertilizing during the season may cause extensive growth in late summer, making the plant more vulnerable to winter injury.

"Phostrogen" fertilizer has a 14-10-27 analysis and is comprised of potassium nitrate, ammonium phosphate, urea, calcium and magnesium sulphates with trace elements.

It appears it's availability is limited to certain countries and it is a slow-release fertilizer that is applied around the base of plants. To my knowledge, there aren't many commercial vineyards that are currently using slow-release fertilizers because of its high cost.

Rather than spending your money on slow-release fertilizers, I'd strongly recommend you make an application of "Mycohhrizae" to your roots. Mycohhrizae is a beneficial fungus that attaches itself to the roots of plants and helps the roots absorb more of the available nutrients and water in the soil. It forms a symbiotic relationship with the host plant and will help the plant forever. I've seen it improve the growth and yields of many commercial agricultural crops. It's been shown that it also helps protect the host plant against root-invading nematodes.

IF you need further information, please feel free to contact me directly and I'll be more than happy to help.

Hope this information was of some help. GOOD LUCK!

-Certified Professional Crop Consultant with over 30 years of experience and a Degree in Plant Science

If you'd like to find out more about mycohhrizae, please visit this site: http://edis.ifas.ufl.edu/pdffiles/ag/ag1...