How to Use Mosquito Dunks and Bits Correctly

🧰 What You'll Need

Mosquito DunksMosquito BitsWatering canScissors

📋 Steps

Identify all standing water sources

Walk your entire yard: flower pot saucers, birdbaths, clogged gutters, low spots in lawn, tarps, wheelbarrows, children's toys, tree holes, and rain barrels. Any water held for 7+ days can produce mosquitoes.

Dump anything that can be emptied

Dumping standing water is faster and more effective than treating it. Tip over any container that doesn't need to hold water. Drain low spots by filling with soil or improving drainage.

Place Dunks in permanent water features

Bird baths you want to keep, ornamental ponds, rain barrels, drainage ditches: place one Mosquito Dunk per 100 sq ft of water surface area. Dunks release Bti for 30 days. Completely safe for fish, birds, frogs, and pets.

Use Bits for soil and organic matter

Mosquito Bits can be sprinkled on potted plant soil (kills fungus gnat larvae), along water edges, and on wet organic material. For large areas: soak Bits in water for 30 minutes, strain, use the water to water plants.

Check and replace monthly

Dunks last approximately 30 days. Replace in May, June, July, and August for full-season coverage in most US climates.

💡 Pro Tips

Mosquito Bits dissolve faster than Dunks — use Bits for quick kill (they work in 24-48 hours) and Dunks for 30-day sustained treatment
Even very clean-looking water in an ornamental pot saucer can produce 30+ adult mosquitoes — don't overlook these sources
Bti doesn't affect adult mosquitoes — combine with vegetation spray (bifenthrin) for comprehensive adult population control

💰 Cost to Fix This Problem

Approach	Typical Cost	Best For
DIY materials only	$30–$80	Mild or early-stage infestations
Professional service (one-time)	$75–$150/visit	Active infestations or when DIY has already failed
Ongoing service contract	$400–$800/yr	Prevention and long-term peace of mind

Approach

Typical Cost

Best For

DIY materials only

$30–$80

Mild or early-stage infestations

Professional service (one-time)

$75–$150/visit

Active infestations or when DIY has already failed

Ongoing service contract

$400–$800/yr

Prevention and long-term peace of mind

Costs vary by region, property size, and severity. Get at least two quotes before hiring.

✅ How to Know It's Working

Pest control success is measured in weeks, not days. Here's what to look for:

Week 1–2: You may see increased activity as pests are flushed from hiding. This is normal.

Week 2–4: Activity should drop noticeably. Bait traps or sticky monitors should show declining counts.

Week 4–6: New activity near zero. Any resurgence means a population was missed or re-introduction occurred.

💡 Monitoring tip: Place sticky traps in corners and along walls before you start treatment. Counting catches weekly gives you objective data on whether the population is declining.

👷 When to Call a Professional

DIY is appropriate for small, contained infestations caught early. Call a licensed professional when:

You've tried DIY twice with no lasting improvement

The infestation involves a wall void, crawlspace, or area you can't safely access

There's a health risk involved (hantavirus, anaphylaxis risk, etc.)

The problem covers more than one room or a large outdoor area

You have children, elderly, or immunocompromised individuals in the household

⚠️ Rule of thumb: If you've spent more on DIY materials than a professional visit would cost, it's time to call.

❓ Frequently Asked Questions

How quickly do mosquitoes breed in standing water?

Eggs hatch within 24-48 hours. Larvae become flying adults in 7-14 days. A single female can lay 100-200 eggs in as little as a bottle-cap of water. Weekly elimination of standing water breaks this cycle.

What about standing water I cannot drain?

Apply Bti mosquito dunks, which treat 100 square feet of water for 30 days and are safe for fish, birds, and pets. For ornamental ponds, mosquito fish provide biological control by consuming larvae.

Do gutters contribute to mosquito breeding?

Clogged gutters are one of the most overlooked breeding sites. Clean gutters at least twice yearly and install guards. After cleaning, flush with water to verify proper drainage since sagging sections hold water.

Can irrigation systems create mosquito breeding habitat?

Irrigation systems themselves do not, but catch basins, valve boxes with pooled water, and low spots that remain wet for 7+ days can. Adjust irrigation to prevent standing water and treat collection points with Bti.