Why Your Weed Killer Isn’t Working – and How to Fix It

You’ve sprayed your field, waited a few days… and the weeds are still standing tall. It’s frustrating—but you’re not alone. Many farmers and gardeners face this problem when using herbicides, especially for the first time.

If your weed killer isn’t doing its job, here’s a breakdown of the most common reasons—and how to fix them using Herbishield products the right way.

1. Wrong Timing of Application

The Problem:
Spraying herbicide when weeds are dormant, stressed, or during rain reduces absorption.

Fix It:

  • Apply when weeds are actively growing (warm temperatures, not water-stressed).
  • Avoid spraying before or during rain.
  • Best times: Early morning or late afternoon on dry days.

2. Incorrect Mixing Ratio

The Problem:
Using too much water or too little product weakens the formula.

Fix It:

  • For Herbishield: Mix 10–20 ml of product per 1 liter of water.
  • Always use clean water and measure properly.

3. Using the Wrong Product Type

The Problem:
Using a contact herbicide like Glufosinate when a systemic solution like Glyphosate is needed—or vice versa.

Fix It:

  • Use Glyphosate for root-deep, long-term weed control.
  • Use Glufosinate for quick surface kill and spot treatments.
  • Still unsure? Compare the two here.

4. Poor Spray Coverage

The Problem:
Not spraying enough herbicide or missing parts of the weed.

Fix It:

  • Spray evenly on the entire leaf surface, especially the tops.
  • Use a knapsack sprayer or fine mist nozzle for best results.
  • Avoid windy conditions that may cause drift.

5. Spraying Weeds That Are Too Mature or Too Small

The Problem:
Old, woody weeds or very young sprouts may not absorb the herbicide well.

Fix It:

  • Apply when weeds are 4–8 inches tall, before they flower or seed.
  • For mature weeds, use a stronger dose and allow 7–14 days for full kill.

6. Soil or Weather Conditions Interfering

The Problem:
Dusty, hard, or waterlogged soils can reduce herbicide effectiveness, especially with root-absorbed products.

Fix It:

  • Spray only when soil is moist but not soaked.
  • Avoid extreme heat, drought, or overly acidic/alkaline conditions.

Bonus Tip: Not Giving It Enough Time

Some herbicides, especially Glyphosate, don’t show instant results. It can take up to 14 days for full effect.

Conclusion: Trust the Process, Apply it Right

Weed control is a science, and even the best herbicides need the right conditions to work. By following the guidelines above, you’ll get the most out of every drop of Herbishield—and see your weeds disappear for good.

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