All grape cultivars have similar phosphorus and potassium requirements. Some types of grapes may need greater amounts of nitrogen to perform well. Soil pH preferences, however, differ considerably. ?Some grape varieties require an acidic soil with an ideal pH of 5.5. They have a relatively high iron requirement and iron solubility increases under acidic conditions. Other types of vinifera varieties prefer the soil pH to be about 6.5. 

Once established, grapevines can be productive for 40 years or more. Adequate soil preparation before planting will contribute to successful vine establishment. In this article, we review how to plant and care for grape trees and vines and use fertilizer for grapes to obtain the highest yield.

best fertilizer for grapes

Below we review the best two fertilizers for grapes

1. Grapes

This unique liquid formula from YARAFERT designed for grape crops utilizes synthetic technology and specific chemicals to enhance production quantity and increase sugar concentration in fruits. It is applied during the final stages of ripeness to promote early ripening and enhance fruit coloration. This compound is specially formulated to stimulate and improve grape crop colouring, serving as an alternative to traditional colouring compounds like Antheral, which can lead to excessive grape grains and diminish the crop’s export value. It ensures the highest yield, top-quality specifications, and extended storage life. 

Packed with microelements such as zinc to boost oxins’ biological processes. Additionally, it contains magnesium to enhance leaf efficiency in photosynthesis. By activating enzymes and promoting the production of carotenoids and vitamin C (ascorbic acid) through the presence of manganese. Please note that this formula should not be used for irrigation or on any other crop. It is recommended not to mix it with any other substance to preserve its properties.

This fertilizer for grapes features:

• Liquid Plant fertilizer produced from pure raw materials
• Increase the quantity and quality of production
• Free chlorine and sodium
• Designed for application by foliar spray and irrigation system

Chemical composition of  fertilizer for grapes 

1. Copper (Cu): 1.5 %
2. Magnesium (Mg): 0.5 %
3. Manganese (Mn): 0.5 %
4. Zinc: 0.5 %

Zinc (Zn) is a key nutrient for fruit set, and magnesium is essential for chlorophyll development, and converting nitrogen to a usable form inside the plant. If these nutrients are low, they will impact the vine’s ability to produce grapes.

Read more: Types of Fertilizers

2. NPK  fertilizer for grapes

Grapevines remove a substantial amount of nutrients from the soil, and as deep-rooted perennials, they depend on proper nutrient management to replace what they remove. As such, a well-designed nutrient management program, including soil testing, is crucial to maximize Grape production.

Nitrogen (N) is a primary requirement for growth of all plants and grapes are no exception. For the most consistent supply of N throughout the season, growers should use a slow-release nitrogen source such as urea or UAN. These sources release N into the soil in a form that roots can readily absorb, but require microbe-mediated conversion processes to be converted to ammonium and nitrate before uptake.

Phosphorus (P) and potassium (K) are also critical for vine growth and maximizing fruit production. For best results, growers should use a soluble source of these elements and apply them in the spring or early summer as a top dress or through fertigation.

YARAFERT provides different concentrations of NPK Suspensions fertilizers such as:

NPK Suspensions fertilizer 10-65-10

NPK Suspensions fertilizer 10-10-40

NPK Suspensions fertilizer 25-25-25

NPK Suspensions fertilizer 40-10-10, and others.

How to apply fertilizer for grapes

Before planting

Prior to planting, it is essential to conduct a soil test six months to one year in advance. Based on the results, add the recommended amount of limestone to adjust the pH level. It is important to note that liming should not raise the pH above 5.5 for American varieties or 6.5 for European varieties. If magnesium levels are below optimal and the pH needs to be increased, dolomitic limestone is recommended as it contains both calcium and magnesium. In cases where the pH level is adequate but magnesium levels are low, incorporate magnesium salts . Retesting the soil every 3 years is advised to monitor pH levels.

If the soil test indicates low phosphorus levels, apply triple superphosphate or bonemeal at the recommended rates per 100 sq. ft. For low potassium levels, add potassium sulfate accordingly. Ensure all necessary amendments are mixed into the soil to a depth of 6 to 8 inches. A final soil test should be conducted one month before planting to confirm the soil conditions.

Read more: Best Starter Fertilizer

In the first three years

1. In the first year of planting, apply 2 ounces (1/4 cup) of 10-10-10 per vine without a soil test, soon after growth begins, and repeat the process about 4 weeks later. Spread the fertilizer evenly over an area 4 to 5 feet in diameter.

2. For the second year, apply 4 ounces (1/2 cup) of 10-10-10 per vine without a soil test, soon after growth begins, and again about 4 weeks later. Spread the fertilizer evenly over an area 4 to 5 feet in diameter.

3. Starting from the third year and for older vines, apply 1/2 lb. (1 cup) of 10-10-10 per each European grapevine or 1 pound (2 cups) of 10-10-10 per American grapevine at bud break without a soil test. Spread the fertilizer evenly over an area 3 to 5 feet wide on each side of the vine.

tips for apply fertilizer for grapes

If soil test results show that potassium and phosphorus levels are above optimum, only apply a nitrogen source to the vines. Urea (46-0-0) at 2 to 3 ounces (1/2 cup) or bloodmeal (12-0-0) at 8 ounces (1 ½ cups) per vine will provide the necessary nitrogen. Excessive vegetative growth indicates the need to reduce the nitrogen amount by half or omit it entirely for one to two years.

Consider applying borax every 3 years, as it may be beneficial. Use not more than ¾ ounce (about 2 tablespoons) of Borax (10 to 12% boron) per 100 sq. ft. Excess boron can harm plants. Dissolve Borax in water and spray it onto the ground. Remember to strain out sediments after Borax has dissolved to prevent damage to the sprayer. Note that plants fertilized with natural/organic sources of nutrients usually do not need additional boron.

• Analyzed soil test results to determine excessive potassium and phosphorus levels, recommending the application of specific nitrogen sources to optimize vine growth.
• Provided tailored recommendations for nitrogen sources such as Urea (46-0-0) and blood meal (12-0-0) based on vine requirements and soil test findings.
• Advised on adjusting nitrogen application rates in response to excessive vegetative growth, ensuring optimal vine health and productivity.
• Implemented a strategic borax application schedule every 3 years to enhance soil fertility and plant health, while preventing potential harm from excess boron.

Read more:  Best Organic Fertilizer