Enter Garden and Trap Details
Example Scenarios
| Area | Setting | Activity | Plan | Suggested traps | Notes |
|---|---|---|---|---|---|
| 300 ft² | Open beds | Low | Hotspots only | 2–4 | Start near droppings, then expand outward. |
| 500 ft² | Greenhouse | Medium | Perimeter + interior lanes | 6–10 | Place along walls and behind benches. |
| 45 m² | Shed / garage | High | Perimeter only | 10–18 | Seal gaps and remove stored feed spills. |
Formula Used
The recommendation starts with a baseline trap density by activity level:
- Low: 1 trap per 20 m²
- Medium: 1 trap per 10 m²
- High: 1 trap per 5 m²
Then the calculator applies practical multipliers:
Spacing is estimated using sqrt(area_m² / traps). Expected captures use a bounded probability model with diminishing returns across days.
How to Use This Calculator
- Measure your garden area, then select the correct unit.
- Pick the setting and activity level based on visible signs.
- Choose a placement plan that matches your available routes.
- Select trap style, bait, and sanitation level honestly.
- Set checks per day and trapping days, then press Submit.
- Place traps flush to walls, with trigger toward travel paths.
- Download CSV or PDF to document your plan and results.
Trap Density Benchmarks
Planning begins with density targets tied to signs. Low activity uses one trap per 20 m², medium uses one per 10 m², and high uses one per 5 m². A 500 ft² bed is about 46.45 m², so the medium baseline is roughly five traps before modifiers. Greenhouses and sheds often need more traps because warmth, cover, and stored feed increase contact.
Placement Geometry and Spacing
Spacing is estimated from coverage: spacing equals sqrt(area ÷ traps). For 46.45 m² with nine traps, grid spacing is about 2.27 m. Perimeter spacing assumes a square footprint where perimeter equals 4 × side length. The same example gives about 27.3 m of edge, so nine traps average about 3.03 m apart along walls and borders.
Check Frequency and Reset Discipline
Frequent checks reduce bait drying, improve reset speed, and limit odor. The model boosts expected performance by about 10% for each extra daily check beyond one, capped near 30%. Checking twice daily for seven days keeps more traps active and reduces missed events. Pair checks with hygiene: remove food scraps, sweep spilled seed, and refresh bait sparingly. For heavy pressure, rotate bait weekly and reposition traps nightly until sign intensity drops and catches stabilize across whole area.
Cost Planning and Inventory Control
Cost equals price per trap multiplied by recommended quantity. At $1.50 each and twelve traps, the estimate is $18.00. Keep 10% spares for damaged units or quick relocation to new hotspots. Record locations, dates, and captures to spot repeat corridors. Good records show when you can reduce density or extend trapping days safely.
Risk Controls and Integrated Measures
When pets or children are nearby, the tool adds a 1.10 safety factor for fewer safe placements. Prefer covered tunnels or secured boxes, and set traps flush to walls with triggers facing travel lines. Expected captures follow diminishing returns: captures = traps × (1 − (1 − p)^days). Combine trapping with sealing gaps, reducing clutter, and compost management for lasting control.
FAQs
1) How do I choose the activity level?
Use Low for occasional droppings or minor nibbling. Use Medium for repeated fresh signs weekly. Use High for frequent sightings, heavy droppings, or daily damage near beds, compost, or storage.
2) Where should I place snap traps outdoors?
Place traps along edges, walls, fences, and bed borders where mice run. Keep the trigger facing the travel path, and shelter traps from rain using boards, tunnels, or boxes.
3) What bait works best for garden mice?
Sticky baits like peanut butter hold well and reduce theft. Chocolate can improve attraction in cool weather. Use a tiny smear; large bait piles invite ants and distract from the trigger.
4) How often should I check and reset traps?
Check at least once daily. Twice daily is better when activity is medium or high, because it keeps traps working, reduces odor, and improves documentation of what is happening.
5) What if I get zero captures after two nights?
Move traps closer to droppings, rub marks, or entry gaps. Remove competing food, refresh bait, and add a few traps to hotspots. If signs persist, inspect for new access points.
6) Can I reuse traps, and how do I clean them?
Yes. Wear gloves, remove debris, then wash with hot soapy water and dry fully. For odor control, wipe with diluted disinfectant and rinse. Replace damaged triggers to keep performance consistent.