Applying Weed Control Best Practices in Tucson Requires Following a Strict Protocol

Rigo Pest Prevention has been implementing weed control best practices in the entire Tucson metro area since 2008, some 17 years ago. Before this, Rigo himself had a 20+ years career  in treating weeds and pest in the region. From this experience, the company has created a full playbook on how to control weeds in the backyards (and front yards) of Tucson.

We’ll share here the highlights of the protocols we use to get your property rid of these unsightly weeds and restore your yards to their xeriscaped beauty.

1. Identification and Targeting

Our first step is to identify the type of weeds.

In our arid desert climate, not all weeds grow well. But those resistant enough to put up a good fight definitely fight to survive and spread. Our weed control specialists focus on aggressive, drought-resistant species: Common Purslane, Common Sowthistle, Russian thistle (tumbleweed), London Rocket, Pigweed, Spurges, Clovers, and crabgrass.

Our weed control specialists also differentiate between annuals and perennials. Both require their own treatments.

2. Pre-Emergent Herbicide Application (Fall & Spring)

“Pre-emergent” refers to a class of herbicides designed to stop weeds before they sprout above the ground. These herbicides target seeds during germination. They work by killing the new growth before it breaks through the soil surface.

How do pre-emergent herbicides work in practice?

In Tucson, some weeds—especially annuals like Sahara mustard, London Rocket, spurge, and foxtail—germinate after seasonal rains. Pre-emergent herbicides form a chemical barrier in the top layer of soil. When a seed tries to germinate and push a shoot or root through that barrier, it fails. The plant dies before it becomes visible.

Our weed control experts use pre-emergent herbicides like Pendulum or Spectacle in late fall (October–December) while applying Barricade in early Spring (March & April) to prevent seed germination. They target growth areas before seasonal rains trigger weed growth.

3. Post-Emergent Herbicide for Active Weeds

Once the weeds are up, pre-emergent products are no longer useful—your yuard would need a post-emergent treatment to take them down.

Post-emergent herbicides are chemical treatments designed to kill weeds that have already emerged from the soil—plants that are visible and actively growing. These herbicides work by entering the plant through its leaves or stems, then disrupting key biological processes like photosynthesis, enzyme production, or cell growth. The weed dies from the inside out, usually over a period of several days to a few weeks.

Our weed control specialists apply non-selective herbicides like Tribune or Glyphosate (e.g., Roundup) on actively growing weeds in spring and summer. We add surfactants to improve absorption in dry conditions.

4. Seasonal Timing Strategy

Weeds don’t grow year-round—They germinate in bursts. In Tucson’s climate, most weeds emerge in response to specific seasonal triggers, especially winter rains (Dec–Feb) and monsoons (July–Sept).

By anticipating these windows, we apply pre-emergents just before germination and post-emergents shortly after emergence. We target weeds when they’re most vulnerable and avoid wasting our time (and your money) during dormant periods.

Applying weed control substances year-round without regard for growth cycles would waste product, increase chemical load, and miss the critical window when treatments are most effective.

In sum, we apply pre-emergent every 6 months (there are our spring & fall applications), and spot-treat emerging weeds with post-emergents on a quarterly rotation (every 3 months).

5. Regulatory Compliance & Environmental Safety

Because of the fragility of our desert ecosystems, the Arizona Department of Agriculture has published stringent regulations on pesticide use. Our weed control specialists are duty-bound by these rules, and follow them “religiously”.

But on top of the regulatory layer, we also have ethical concerns. For instance, we avoid overspraying near water sources because we need to prevent runoff. We also use low-volatility formulations because they reduce the risk of vapor drift in hot, dry conditions.

What is volatility in herbicides? Volatility refers to the tendency of a herbicide to evaporate into a gas after application. Once vaporized, it can move off-target with the wind or thermal currents—this is called vapor drift. In high heat (above 85°F) and low humidity, volatility increases significantly. That means would control specialists would have to use more product to do the same work, or their work would be less efficient. Notwithstanding the consequences for the environment.

6. Educating Our Clients on Prevention

As specialists in weed management services, a big part of our job is to bring about understanding of best practices in our clients mind. To this effect, we offer our clients desert landscaping recommendations, especially with native, drought-resistant plants. We also teach our clients about proper irrigation practices as a way to minimize weed growth. Minimizing weed growth also means less weed control treatments. As our grandmothers used to say, an ounce of prevention is worth a pound of cure.

These are the big rules in our playbook. We have been one of Tucson’s favorite pest control and weed control company 6 years in a row, since the beginning of the Arizona Daily Star contest. Don’t wait to see your yard covered in green weeds when it should be a manicured xeriscape: call Rigo Pest Prevention and sign up for weed control service before the season is on us!

Weed Control FAQ

1. Why do weeds grow so aggressively in Southern Arizona?

Because Tucson’s desert weeds are adapted to sprout rapidly after seasonal rains. Dormant seeds lie in the soil year-round and respond immediately to winter or monsoon moisture, especially in disturbed or irrigated areas.

2. What is pre-emergent herbicide, and how does it work?

Pre-emergent herbicides form a chemical barrier in the soil that kills weed seeds at germination—before they break the surface. They must be applied before seasonal rains to be effective.

3. When should I apply pre-emergent herbicides in Tucson?

Twice a year: once in late fall or winter (before winter weeds germinate) and again in late spring or early summer (before monsoon weeds emerge).

4. What is a post-emergent herbicide, and when is it used?

Post-emergent herbicides kill visible, growing weeds. Contact types kill what they touch; systemic types kill the whole plant by entering through the leaves and traveling to the roots.

5. Why use a seasonal timing strategy instead of treating weeds year-round?

Seasonal timing targets weeds when they’re most vulnerable and reduces overuse of herbicides. Year-round blanket spraying wastes product, increases costs, and raises environmental risks.

6. What types of weeds are most common in the Tucson area?

Problematic species include buffelgrass, Sahara mustard, Russian thistle (tumbleweed), London rocket, and bermudagrass—all fast-growing and drought-adapted.

7. What certifications should a weed control company in Arizona have?

A company must hold:

• Certified Applicator (CA) License: Legal authority to apply herbicides

• Certified Qualified Applicator (QA) License: Allows for operational oversight and regulatory compliance
  These are issued by the Arizona Department of Agriculture – Pest Management Division (PMD).

8. What’s the difference between natural and synthetic weed control methods?

Natural options use OMRI-approved herbicides and manual removal, ideal for sensitive areas. Synthetic methods use chemical pre- and post-emergents, effective for long-term, large-scale suppression.

9. How do low-volatility herbicides help in hot, dry climates like Tucson?

They’re formulated to resist vaporization in high heat, reducing drift and off-target damage. This ensures safer, more accurate application even in extreme conditions.

10. Why hire a local expert like Rigo Pest instead of a general landscaper?

Because weed control in Arizona requires knowledge of desert soil, invasive plant cycles, licensing laws, and product selection. Rigo Pest uses targeted treatments aligned with Tucson’s environmental and seasonal patterns.