Timing Herbicide Applications

The Complete Guide to Timing Herbicide Applications for Food Plots

By Plot Blaster

 

When managing food plots for wildlife or hunting properties, one of the most important—and often misunderstood—aspects of preparation is timing your herbicide applications correctly.

At Plot Blaster, we’re constantly asked about how, when, and why to spray herbicides in food plots. The answers depend on your goals, region, tools, and planting method, but they always come back to five key questions:

The 5 Keys to Herbicide Timing in Food Plots:

 

1. Timing in Reference to Planting
2. Timing Before or After Mowing
3. Timing in Association with Weather
4. Ideal Time of Day
5. Timing for Maximum Effectiveness

Whether you’re planting clover, brassicas, or cereal grains for fall, understanding these five principles can save you time, money, and frustration—and dramatically increase the success of your food plots.

 

1. Timing in Reference to Planting

Let’s start with one of the most frequent questions:

 

“When should I spray in relation to planting my food plot?”

This is critical. Everything about your herbicide application—when, what, how much—depends on when you plan to plant.

Set Your Planting Window

 

Before anything else, set your planting date. From there, work backward to create a preparation timeline that fits your method of planting (conventional or no-till) and your expected frost date.

• For fall food plots, a common rule of thumb is to plant 60 days before your first anticipated frost.
• This gives you time for herbicide effectiveness, soil preparation, and any needed second passes.

Conventional Tillage Timeline

 

 

If you’re using conventional tillage, the preparation timeline might look like this:

• 6–8 weeks before planting: Apply herbicide for burndown.
• 4–6 weeks before planting: Till and incorporate dead matter.
• 1–2 weeks before planting: Conduct final seedbed prep and soil amendments.
• Plant at your desired window.

Conventional methods require more time because green, living vegetation is harder to till and demands more soil energy to break down. Dead plant matter is easier to incorporate and actually helps preserve soil structure and microbial life.

 

No-Till or Spray-and-Plant Timeline

 

If you’re using a no-till method, your timing can be far more flexible. Herbicide is still essential for controlling competition, but you don’t need multiple tillage passes.

 

Here’s a common no-till timeline:

• 10–14 days before planting: Apply herbicide for full burndown.
• 7–10 days later: Broadcast seed directly over the dead vegetation.
• Optional: Mow over the area to crimp vegetation and cover seed.

This is often referred to as the “spray, throw, and mow” method—an efficient, regenerative approach that minimizes soil disturbance and maximizes moisture retention.

Regional Example: Southeastern U.S.

In the Southeast, we recommend:

• Burndown spraying before Labor Day
• Planting mid-September

This allows enough time for the herbicide to kill off unwanted growth and for dead vegetation to dry and settle, creating an ideal planting bed.

2. Timing Before or After Mowing

Another hot topic is mowing:

 

“Can I mow and spray on the same day?”

Technically, yes—but it’s not ideal.

Why You Should Wait to Spray After Mowing

We strongly recommend waiting 7 to 10 days after mowing before applying herbicide. Here’s why:

1. Reduced Surface Area: Mowing removes the plant’s most active, thriving foliage—exactly the part you want your herbicide to contact. After mowing, there’s less green material for the herbicide to bind to.
2. Thatch Barrier: Mowed vegetation creates a layer of thatch that may shield young weeds and grasses from herbicide contact. These plants will continue to grow underneath while your herbicide lies dormant on the surface.
3. Incomplete Kill: If the herbicide can’t reach the full population of unwanted plants, you risk a partial kill, which often requires a second, more aggressive (and expensive) application.

 

What to Do Instead

 

• Mow the plot if needed.
• Wait 7–10 days to allow vegetation to regrow and new shoots to emerge.
• Apply herbicide to ensure full contact and maximum absorption.

 

When Mowing Might Be Unnecessary

One of the benefits of using the Plot Blaster sprayer is that mowing isn’t always needed before spraying. Thanks to its:

• High clearance,
• Adjustable nozzles, and
• Fine droplet control,

…you can spray over tall, dense vegetation without clogging nozzles or missing spots. Once sprayed, overgrown plots begin to collapse as vegetation dies back naturally—eliminating the need for mowing in many cases.

 

3. Timing in Association With Weather

Weather is a major player in herbicide effectiveness. Even the best herbicides can fail if applied under the wrong conditions.

Wind

Spraying in windy conditions increases your risk of:

• Drift, which moves the herbicide off target and can kill beneficial plants
• Inconsistent coverage, leaving spots untreated
• Wasted product, reducing cost-effectiveness

Always check your local forecast. Winds under 5 mph are ideal for most broadcast applications.

 

Rain

Rain is a bigger concern than most people realize.

• If it rains too soon after spraying, your herbicide may be washed off before the plant absorbs it.
• This leads to incomplete kills, stunted weeds, and often the need to respray.

Follow the Label

Your herbicide’s label will tell you how long it needs to dry or “set” before rain. This is often 1–4 hours but can vary.

Use Adjuvants for Rain Risk

If rain is a possibility, use a spreader-sticker adjuvant like SoluMax 5, which helps herbicides adhere to foliage and penetrate waxy plant surfaces—even in marginal weather.

 

4. Best Time of Day to Spray Herbicide

We’re often asked:

 

“Is there a best time of day to apply herbicides?”

The short answer: Midday is usually best, but it depends on your local conditions.

Morning Applications

 

• Morning dew can dilute or wash off herbicide on contact.
• Early spraying may cause the solution to bead up and roll off, reducing contact and effectiveness.

 

Afternoon Applications

• Many regions, especially the South, experience pop-up thunderstorms in the late afternoon.
• Spraying too close to these events can negate the application and waste product.

Midday Applications

When possible, plan to spray:

• Between 10 a.m. and 2 p.m.
• On dry, calm days
• With minimal wind and no chance of rain

This ensures that plants are dry, weather is stable, and absorption is maximized.

 

5. Timing for Maximum Effectiveness

Finally, let’s talk about a question that’s rarely asked—but incredibly important:

“When are plants most vulnerable to herbicide?”

The Best Time to Spray: When Plants Are Thriving

Your herbicide will be most effective when plants are actively growing and healthy.

That may seem counterintuitive. You might think, “If the weeds are stressed from drought, now’s the time to hit them hard.”

Wrong. Drought-stressed plants go into a dormant state, closing their pores and reducing chemical uptake. Spraying during stress can lead to a partial or failed kill, forcing you to reapply.

What to Do Instead

• Wait for a rain event to rehydrate the plants.
• Then, spray 24–48 hours later when growth has resumed.
• This ensures that plants are actively uptaking water and nutrients—and herbicide.

This principle applies to everything from fence rows to full-size food plots. Always spray when the plant is healthy and growing, not stressed or wilted.

Final Thoughts: Make Timing Work for Yo

Herbicide application isn’t just about picking a day and spraying. It’s about:

• Planning your plot calendar
• Understanding weather patterns
• Working with your planting method
• Reading your plants’ health cues
• Using tools like Plot Blaster to maximize efficiency

If you follow the five principles above, your herbicide applications will be more effective, efficient, and less costly—giving your food plots the best chance for success.

Why Choose Plot Blaster?

At Plot Blaster, we’ve designed our sprayer systems with real-world food plotters in mind—people who are tired of unreliable, overpriced equipment and want a dependable, adjustable, and easy-to-use sprayer that can handle everything from fence rows to full-acre plots.

• High clearance and powerful nozzles
• Adjustable pressure and coverage
• Perfect for both conventional and no-till methods

Whether you’re burning down thick plots or touching up around the edges, Plot Blaster helps you do it right—the first time.

Need help timing your applications or choosing the right setup for your property?

Contact us for help any time!