How do I use Gold Roach Spray correctly?

Fit the extension tube into cracks, crevices, and voids where roaches actually hide — under and behind sinks near pipe penetrations, beneath appliances, and behind cabinets — and inject a short burst so the dry spray carries into the void rather than wetting the open surface. Hit visible roaches directly for knockdown, but the real work happens in the cracks you can't see. Let treated areas dry undisturbed, and never spray it over or near a gel or liquid bait, since the residue will repel roaches away from bait you wanted them to carry back to the colony.

Does Gold Roach Spray actually work?

For dry crack-and-crevice treatment, yes — the dry propellant genuinely penetrates further into voids than a wet spray, the permethrin knocks down what it contacts, and the pyriproxyfen IGR adds a real reproduction-suppressing effect most contact aerosols don't have. What it can't do is end a heavy, established German-roach infestation by itself. University IPM guidance is consistent that sprays alone — even a well-designed one like this — don't eliminate cockroaches; sanitation and, for real colony control, baiting still matter.

Why do I still see roaches after spraying?

Contact knockdown only kills what the spray directly reaches, and permethrin's repellency can scatter roaches deeper into voids rather than through the treated zone. The IGR works on a different, slower timeline — weeks to months, not days — so persistent sightings shortly after treatment don't necessarily mean failure. But if roaches are still active after several weeks of thorough, harborage-focused treatment, that's a sign the population is established enough to need baiting or professional help.

What does the IGR (pyriproxyfen) actually do, and how long does it take?

Pyriproxyfen is an insect growth regulator, not a knockdown poison — it disrupts the hormones roaches need to mature and reproduce, so nymphs that contact it can't develop into breeding adults and exposed adults become less fertile. That effect builds gradually over weeks to months as more of the population contacts treated cracks, which is very different from the permethrin's immediate contact kill. Judge the IGR on population decline over time, not on how many dead roaches you see the next morning.

Can I use it alongside a gel bait for roaches?

You can use both, but they need separate territory. Gel and liquid baits work because a roach carries the toxicant back to the colony before dying, and a repellent pyrethroid residue nearby will drive roaches away from the bait or kill foragers before they can share it — undercutting the bait's colony-level effect. Treat cracks and voids away from your bait placements with the spray, and leave the bait zones spray-free.

Is it safe to use around my pets?

Remove pets and people from the area before spraying and keep them out until the treated cracks are fully dry and any vapor has cleared — that's when exposure risk is highest. Bengal specifically flags extra caution around cats, which are slower to clear some insecticide compounds than dogs. For the full per-species pet-safety verdict on this product, see the companion review at /is-pest-control-safe-for-pets/gold-roach-spray-by-bengal.

Daniel Brady · NH-Licensed Pesticide Applicator · License #782664

How to Use Gold Roach Spray by Bengal

Workhorse

Permethrin 2.0%Pyriproxyfen (Nylar) 0.05%

Used correctly, Bengal Gold Roach Spray's dry-propellant formula does two jobs a plain contact aerosol can't: the permethrin knocks down roaches and other insects on contact, and the pyriproxyfen IGR keeps suppressing reproduction in the treated void for months afterward. Insert the extension tube into cracks, crevices, and voids — especially around pipe penetrations under sinks — and inject the dry spray back into the space so it travels behind the wall instead of wetting the surface. What it does NOT do is end a heavy, established German-roach infestation by itself; university extension guidance is consistent that sprays alone won't eliminate cockroaches, and heavy application can scatter roaches or undercut a bait placed nearby. Keep applications light and targeted, pair with sanitation and, ideally, a gel bait kept in a separate zone, and if roaches persist after diligent crack-and-crevice treatment, that's your signal to call a professional.

At a glance

Efficacy: Workhorse
Best job: Injecting a dry, non-wetting knockdown-plus-IGR combination deep into cracks and voids behind walls, where wet sprays can't travel as far
Format: Ready-to-use dry-propellant aerosol with an extension tube — no mixing, doesn't wet surfaces
Technique: Moderate technique

The honest verdict

Does this product actually work?

The verdict on this product

WorkhorseModerate technique

Workhorse

A genuine workhorse for dry crack-and-crevice knockdown plus long-tail IGR suppression — not a standalone cure for an infestation already established.

The dry propellant is a real technique advantage — it penetrates cracks and travels behind walls without wetting the surface, and the pyriproxyfen IGR meaningfully suppresses reproduction over months, a genuine edge over a plain contact aerosol. But permethrin is still a repellent pyrethroid: heavy or careless application scatters roaches and can undercut a bait program, and university IPM guidance is consistent that sprays alone won't eliminate an established cockroach population.

Best for

Injecting a dry, no-wetting insecticide-plus-IGR combo deep into cracks, voids, and harborage around plumbing, cabinets, and baseboards.

Skip it for

Expecting the can alone to end a heavy German-roach infestation without sanitation and, ideally, a gel-bait program running alongside it.

Read the label first

What it is — and what it's really for

The label is the law. Here's the honest read on the format, the one job it does well, and the job people wrongly buy it for.

Format

Ready-to-use dry-propellant aerosol with an extension tube — no mixing, doesn't wet surfaces

Indoor / outdoor

indoor

Residual

Permethrin knocks down on contact; the pyriproxyfen IGR is marketed to suppress reinfestation for up to 6 months in treated, undisturbed voids — verify the current label

Target pests

Cockroaches (including German cockroaches), Ants, Centipedes, Crickets, Silverfish, Spiders, Sowbugs, Fleas (the IGR also sterilizes fleas in treated areas)

Best job

Injecting a dry, non-wetting knockdown-plus-IGR combination deep into cracks and voids behind walls, where wet sprays can't travel as far

Active ingredient

Permethrin (2.0%), Pyriproxyfen (Nylar) (0.05%)

Not for (honest)

Ending an established German-roach infestation on its own — even with an IGR, a can still needs sanitation and, for real colony control, gel baiting

The technician's method

The technique walkthrough

Where DIY succeeds or fails is in the placement, patience, and the small pro moves the label never mentions. Follow the label; these are the technique details on top of it.

Moderate technique~10-20 min to apply; contact knockdown in minutes, IGR effect builds over weeksTools:The can's extension tube, Gloves, A flashlight to locate harborage

This can rewards patience and precision — inject into the crack, don't fog the surface, and let the dry propellant do the work of reaching deep behind the wall.

Locate the harborage, not just the roach
Find where roaches actually hide — under and behind sinks (especially where pipes enter the wall), beneath appliances, and behind cabinets — before you spray anything.
Pro move
Check damp, dark areas near a water source first — that's where German roaches concentrate.
Common mistake
Spraying only where you saw a roach cross open floor — that's not harborage.
Insert the extension tube into the crack
Fit the tube into the crack or crevice you're targeting so the dry spray discharges inside the void, not on the open surface.
Inject, don't fog
Trigger a short burst so the dry propellant carries the active ingredient back into the void and behind the wall — this is the technique advantage a dry-propellant can gives you over a wet spray.
Pro move
Exploit the dry propellant: aim into cracks around pipe penetrations and let it travel where a wet spray physically can't reach.
Common mistake
Fogging open surfaces or over-applying — permethrin's repellency scatters roaches and wastes the IGR's slower-acting benefit.
Keep it out of bait zones
If you're also using a gel or liquid bait for roaches or ants, treat spray zones and bait zones as separate territory.
Caution
Never spray this can over or near a bait placement — the repellent residue drives roaches away from the bait.
Let it dry and be patient with the IGR
Allow treated cracks to dry undisturbed. The permethrin's knockdown is fast, but the pyriproxyfen IGR needs weeks-to-months of contact with the population to fully suppress reproduction.
Caution
Keep kids and pets out until dry and vapors clear; Bengal advises extra caution around cats.

Habits that decide it

Do & don't

Inject into cracks, crevices, and voids with the extension tube
Target harborage near moisture and pipe penetrations
Pair with sanitation to remove competing food sources
Let the IGR work over weeks — don't judge it on day one

Don't

Don't fog open surfaces or broadcast-spray
Don't spray over or near a gel or liquid bait
Don't over-apply chasing instant results
Don't treat food-prep surfaces

The honesty moat

Where it works vs. where it fails

No product fixes everything. This is the honest boundary — the situations it genuinely handles, and the ones it simply won't.

Where it works

Roach harborage sits in dry cracks, voids, and pipe penetrations the extension tube can reach
You want reproduction suppression alongside contact knockdown (the IGR advantage)
A handful of visible roaches or ants need fast knockdown
Entry cracks around plumbing need targeted treatment

Where it fails

A heavy, established German-roach population needs to be eliminated by the can alone, without sanitation or baiting
Harborage is damp or gets disturbed (both the dry residual and the IGR work best undisturbed)
It's used as a broadcast spray expecting a surface barrier
The population has already outlasted diligent crack-and-crevice treatment

Don't throw money away

Mistakes that waste the product

Over-spraying or fogging open surfaces

Permethrin's repellency scatters roaches away from the treated area and wastes the IGR's slower, more valuable reproduction-suppressing effect.

Fix

Inject light, targeted bursts into cracks and voids with the extension tube — not open surfaces.

Spraying near a gel or liquid bait

The repellent residue drives roaches away from bait they'd otherwise carry back to the colony, undercutting the bait's colony-level kill.

Fix

Keep spray zones and bait zones in physically separate parts of the home.

Skipping sanitation

Roaches keep breeding on available food and water even while the IGR is suppressing some reproduction — sanitation removes the competition.

Fix

Remove food and water sources alongside treatment, not instead of it.

Judging the product after a few days

The IGR's reproduction-suppression effect builds over weeks to months, not overnight — early impatience leads to unnecessary re-treatment.

Fix

Treat harborage thoroughly once, then give the IGR weeks to work before reassessing.

Calibrated expectations

What to expect — and when

This is a two-speed product: fast contact knockdown today, slow reproduction suppression over the following months — judge each on its own timeline.

Minutes after application
Direct contact knocks down roaches and other listed insects quickly.
First 1-2 weeks
Fewer visible roaches as the residual in treated cracks keeps working and the IGR begins affecting the developing population.
Weeks to months
The pyriproxyfen IGR continues suppressing reproduction in treated voids — full population decline is gradual, not overnight, and depends on thorough harborage coverage.

When results plateau

Results plateau when harborage goes untreated or the population is large enough that sanitation and baiting are needed alongside the spray — the IGR slows reproduction, but it doesn't replace removing food/water sources or, for an established infestation, professional treatment.

Know the ceiling

When to stop DIY & call a pro

The dry spray plus IGR combination is one of this hub's stronger aerosols, but it still has a ceiling. These are the honest signals it's been reached:

Roaches persist after diligent, harborage-focused crack-and-crevice treatment
An established German-roach population combines behavioral and physiological resistance that a consumer aerosol, even with an IGR, can't reliably overcome alone.
You're seeing roaches during the day
Daytime sightings typically mean the hidden population has grown large enough to push individuals out of harborage — a sign of an infestation beyond spot treatment.
The problem is in a multi-unit building
Roaches migrate between shared walls and units; individual treatment can't control a building-wide population.
You see large black ants indoors or moisture-damaged wood
Those point to carpenter ants nesting in structural wood — a wood-destroying pest that needs professional inspection, not a spot spray.

When crack-and-crevice treatment isn't holding the line, Anchor's licensed NH technicians identify and treat the actual harborage and colony with targeted professional methods. Free inspection, same-day service across southern and central New Hampshire.

Roaches still active after careful crack treatment?

Get a Free inspection (603) 785-0118

Before you treat

Is it safe for pets & kids?

The short version lives here; the full per-species verdict lives on this product's pet-safety page.

This is a dry-propellant pyrethroid-plus-IGR aerosol; remove pets and people before spraying and keep them out until it's dry and vapors have cleared. Bengal specifically advises extra caution around cats.

Re-entry: Keep children and pets out of the treated area until fully dry and the space is ventilated.

If there's an exposure, call

ASPCA Animal Poison Control: (888) 426-4435 Pet Poison Helpline: (855) 764-7661 Northern New England Poison Center: (1-800) 222-1222

See the full per-species pet-safety verdict for this product

New Hampshire context

German roaches in New Hampshire homes

German cockroaches can't survive a New Hampshire winter outside a heated structure, so an indoor sighting almost always means an established harborage inside the building, not an occasional outdoor invader. Gold Roach Spray's dry, crack-and-crevice technique suits the pipe penetrations and cabinet voids where NH roach populations concentrate, but a population that's outlasted careful treatment usually needs baiting or professional help. Anchor Pest Services treats the source across Manchester, Nashua, Concord, and the surrounding towns.

Service area

Southern New Hampshire

Anchor Pest Services · NH license #782664 · NEPMA member · family-owned since 2017.

Common questions

Frequently asked

Sources & further reading(5)

[1]
US EPA, Pesticide Product Label — Bengal Dry Roach Spray (Reg. No. 68543-20)
Verified actives (permethrin, pyriproxyfen), dry aerosol format, target pest list
epa_labelverified 2026-07-14
[2]
Bengal Gold Roach Spray — Safety Data Sheet
Confirmed concentrations (permethrin 2.0%, pyriproxyfen/Nylar 0.05%), dry-propellant format facts
manufacturerverified 2026-07-14
[3]
UC IPM — Cockroaches (Home & Landscape)
Insecticide sprays alone will not eliminate an established cockroach population
extensionverified 2026-07-14
[4]
NC State Extension — Tips for Effective Ant Baiting
Spraying near or over bait contaminates and repels foragers from the bait
extensionverified 2026-07-14
[5]
NPIC — Permethrin General Fact Sheet
Permethrin pyrethroid class and contact-kill behavior
npicverified 2026-07-14

Written & reviewed by

Verified

Daniel Brady

NH-Licensed Pesticide Applicator · License #782664 (NHDAMF, RSA 430)

Daniel Brady is the New Hampshire–licensed applicator behind Anchor Pest Services, a family-owned pest control company serving the Manchester area since 2017.

Verify license

Last updated July 2026

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Professional Pest Control

When a Can Isn't Enough

A dry-spray-plus-IGR aerosol is a genuine step up from a plain contact can, but it still can't finish an established German-roach infestation. Anchor Pest Services treats the actual source with targeted, licensed methods across southern and central New Hampshire. Family-owned since 2017, NH license #782664.

Get a Free inspection (603) 785-0118

Targeted source treatment, not just spot spraying
NH-licensed applicators (#782664)
Free inspection — same-day service across southern NH

NH License #782664 · No obligation · We answer in person

Keep Exploring

How to Use Gold Roach Spray by Bengal

Does this product actually work?

What it is — and what it's really for

The technique walkthrough

Locate the harborage, not just the roach

Insert the extension tube into the crack

Inject, don't fog

Keep it out of bait zones

Let it dry and be patient with the IGR