Unpacking the science, benefits, and best practices behind foliar applications

Liquid fertilizer has revolutionized modern plant nutrition, and foliar feeding—a method of applying nutrients directly to leaves—has become a go-to technique for many growers. But how effective is this method, and when should it be used instead of traditional root applications?

This comprehensive guide explores how foliar feeding with liquid fertilizer works, when it’s most beneficial, and how to use it properly without damaging plants. Along the way, we’ll introduce high-performance solutions from the YaraFert portfolio, such as Biofast, SULPHOMIN, and Ugarit Grapes, to show how foliar nutrition can elevate plant health and productivity.

What Foliar Feeding With Liquid Fertilizer Means and When to Use It

Foliar feeding is the process of applying liquid fertilizer directly onto plant leaves, allowing nutrients to enter through the stomata and epidermis. This method bypasses soil absorption, delivering faster results when plants show signs of nutrient deficiencies or when root uptake is compromised.

You should consider foliar feeding with liquid fertilizer in the following situations:

• Nutrient deficiencies appear suddenly and need immediate correction (e.g., nitrogen or magnesium).
• Root systems are weak due to compacted soils, waterlogging, or transplant shock.
• Critical growth stages such as flowering, fruit set, or early vegetative development require quick nutrient boosts.
• Soil pH imbalances are limiting nutrient availability despite adequate soil fertilization.

For example, SULPHOMIN, a liquid fertilizer with 45% nitrogen and 15% sulfur, is ideal for quick chlorophyll production during active vegetative phases. It works well as a foliar spray due to its fine particle size and high solubility.

Best Plants for Foliar Liquid Fertilizer Applications

While foliar feeding can benefit many plants, certain crops respond especially well due to leaf morphology and nutrient demand during specific growth stages.

The following plants are excellent candidates for foliar liquid fertilizer applications:

• Fruit Trees and Grapevines
  • Products like Ugarit Grapes provide targeted micronutrients such as manganese, zinc, and magnesium for improved fruit set and disease resistance.
• Vegetables (e.g., Tomatoes, Peppers, Lettuce)
  • Use Ugarit Strawberry (20% P, 25% K) during flowering to promote bloom health and fruit fill.
• Leafy Greens (e.g., Spinach, Kale, Lettuce)
  • Apply nitrogen-dominant foliar sprays such as Ugarit Cereal (15% N, 2% Cu) for fast leaf development and vibrant color.
• Ornamentals (Roses, Geraniums, Bedding Plants)
  • A balanced foliar fertilizer like Biofast (12-12-12 + 24% humic and fulvic acids) supports both leaf growth and flowering while improving nutrient uptake via chelation.

Note: Always spray in the early morning or late afternoon to prevent leaf burn and maximize nutrient absorption.

Read more: Liquid Fertilizer for Vegetables: Boost Growth Naturally

Read more: Liquid Fertilizer for Houseplants: Simple Feeding Tips

How to Mix and Spray Liquid Fertilizer Without Damaging Leaves

Foliar application is highly effective when done correctly—but it can cause leaf damage or yield loss if misapplied.

Here’s how to properly mix and spray liquid fertilizer for safe, effective foliar feeding:

• Use the Right Concentration
  • Start with a dilution ratio of 1:100 (1 L fertilizer to 100 L water). Adjust based on label instructions and crop tolerance.
  • For micronutrient-rich options like Ugarit Beet, dilute more (1:200) to avoid toxicity.
• pH and Water Quality
  • Ideal spray solution pH: 5.5–6.5.
  • Use clean, chlorine-free water to preserve microbial and nutrient activity—especially when applying organic-rich products like Biofast or Ugarit Multi.
• Spray Volume and Coverage
  • Aim for fine misting, covering both leaf surfaces without dripping.
  • Use low-pressure sprayers to prevent mechanical damage.
• Avoid Direct Sunlight
  • Spray during cooler hours to reduce evaporation and stomatal closure.

Foliar Application Mixing Chart Example:

Common Misconceptions About Foliar Liquid Fertilizer Use

Despite its effectiveness, foliar feeding with liquid fertilizer is often misunderstood. These misconceptions can lead to misuse or missed opportunities.

Let’s debunk a few common myths:

• “Foliar feeding replaces root fertilization.”
  • False. Foliar feeding is a supplement, not a substitute. It corrects deficiencies quickly but doesn’t sustain long-term nutrition.
• “All nutrients can be absorbed through leaves.”
  • Not entirely. While nitrogen, magnesium, and micronutrients are efficiently absorbed, elements like calcium and phosphorus are better absorbed through roots. CALCIMAG (high in calcium) is effective via foliar feeding only in small, frequent doses.
• “More is better.”
  • Overfeeding can cause phytotoxicity. Always adhere to product-specific dilution guidelines.
• “Only the top side of the leaf matters.”
  • Actually, the underside of leaves has more stomata, making it more receptive to nutrient uptake.

Understanding these principles ensures safe and productive use of any liquid fertilizer applied through the foliage.

Read more: How Liquid Fertilizers Work: The Science of Fast Nutrient Absorption

Read more: Best Liquid Fertilizer for Lawns: What to Use and When

How to Measure Results From Foliar Liquid Fertilizer Feeding

To determine whether your foliar feeding efforts are working, it’s essential to track plant response over time. Unlike soil amendments, foliar feeding can show visible effects within days—especially when using fast-acting formulas like SULPHOMIN or Ugarit DKP.

Monitor these key indicators after foliar liquid fertilizer applications:

• Visual Improvements (3–7 days):
  • Greener leaves, improved turgor, reduced yellowing.
  • Micronutrient-rich products like Ugarit Grapes can improve foliage color and luster.
• Tissue Testing (7–14 days):
  • Lab analysis of leaf tissue nutrient levels confirms uptake.
• Growth Rates (2–4 weeks):
  • Faster shoot elongation, thicker stems, earlier flowering.
• Yield Quality (Seasonal):
  • Improved fruit size, shelf life, and uniformity with potassium-rich options like Super DKP (30% P, 60% K).

For high-value crops, keep a feeding log to track application dates, weather, plant stage, and results. This helps refine your foliar feeding strategy over time.

Read more: How to Apply Liquid Fertilizer: Step-by-Step Instructions

Read more: How to Apply Liquid Fertilizer: Step-by-Step Instructions

Conclusion: Foliar Feeding That Works—With the Right Liquid Fertilizer

Foliar feeding with liquid fertilizer is more than a quick fix—it’s a strategic tool that enhances plant vitality during critical phases of growth. Whether you’re correcting deficiencies, pushing for better flowering, or enhancing micronutrient levels, the right application method and product choice matter.

With balanced, crop-specific solutions like Biofast, SULPHOMIN, CALCIMAG, and the micronutrient-targeted Ugarit product line, Yarafert offers tailored foliar feeding solutions for every growing challenge.

Ready to Boost Plant Health With Precision Foliar Feeding?

Browse our full portfolio of YaraFert liquid fertilizers to find the perfect match for your crops and conditions.
Need expert help with spray timing, dilution ratios, or product selection? Contact our team of agronomists today.
Don’t wait for deficiencies to show—feed smarter, faster, and more effectively with foliar liquid fertilizer.