How to use yellow sticky traps: peel, place and replace
Updated: 17 October 2026
The pack is open beside a houseplant, tiny flies are lifting off the compost, and the yellow card still has its film on. How to use yellow sticky traps is three checks: peel every cover, keep the glue in the air just above the compost or on a proper hang, and change the card when you can no longer see yellow. This follows Gardeners' World, the Royal Horticultural Society, and the placement lines on the amazon.co.uk listings in the [yellow sticky traps comparison](/hub/traps/yellow-sticky-traps). We did not run a laboratory catch test. A qualifying purchase can earn a commission at no extra cost to you.
The pack is open beside a houseplant, tiny flies are lifting off the compost, and the yellow card still has its film on.
The pack is open beside a houseplant, tiny flies are lifting off the compost, and the yellow card still has its film on. How to use yellow sticky traps is three checks: peel every cover, keep the glue in the air just above the compost or on a proper hang, and change the card when you can no longer see yellow. This follows Gardeners' World, the Royal Horticultural Society, and the placement lines on the amazon.co.uk listings in the yellow sticky traps comparison. We did not run a laboratory catch test. A qualifying purchase can earn a commission at no extra cost to you.
Our top picks
| Badge | Product | Placement | Double-sided | Mount included | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  aonova aonova 60 yellow cards | Soil or flat | Yes | No | 8.7 | about £5.99 | View offer |
 Blooven Blooven 60 yellow cards | Into soil | Yes | No | 9.2 | about £6.99 | View offer | |
| Alternative |  flintronic flintronic 30 square cards | Hang or soil | Yes | Yes | 7.9 | about £4.99 | View offer |
On this page
Peel the cover before the card goes near anything
A yellow card with the film still on will not catch anything. Blooven and MSR tell you to peel before the card goes into the pot, and MSR says both covers, in line with Super Ninja and Baby Bio. If the sheet is coated on two faces, one peeled side still leaves a dead face. Check the edges after the first film lifts, because a second cover is easy to miss once the plastic already looks yellow.
Heat makes the film stubborn. A lunyoutrio reviewer said the covers were harder to peel after storage above 30°C, which a closed greenhouse can reach on a bright afternoon. Lift a corner with a fingernail rather than folding the glue onto itself. A TRIITECH review warned against touching the glue, and the lnkey listing says to keep children and pets away. Pack choice is on the yellow sticky traps buying guide.
Keep fungus-gnat cards at soil level
Fungus gnats leave damp compost and fly low. Gardeners' World says to hang the trap near the plant or fix it to a cane in the compost, and to keep it near soil level. Blooven's method is peel, then slide into the soil, with the yellow just above the surface. Push the sheet down until the glue disappears and you have buried the catching face.
MSR asks for a slight angle, not a card laid flat on the soil, so water and a settling surface do not press glue into the compost. The aonova listing allows the card in the soil or laid flat, so a flat sheet matches that pack and clashes with MSR. If you lay one flat, the glue still has to face the air. If flies keep emerging, the compost is the next job, on the yellow sticky traps for fungus gnats page.
Hang greenhouse cards just above the leaves
GOTRUST and flintronic tell you to tie through the hole. Lunyoutrio offers stakes or adhesive hooks. A stake in a pot is still a soil-level card if the yellow sits just above the compost. A hook on the glazing, or a tie on a crop wire, earns its place when the insects are up in the foliage.
On a greenhouse bench, set the card just above the leaves and keep the glue off the leaf. A card that slaps wet foliage glues the plant and stops catching flies. Do not use the open garden as the default. Plantura notes that outdoor use from late March can catch beneficial insects. Where a listing still mentions the garden, follow Gardeners' World and the RHS. Flies around kitchen fruit are a different job, on the yellow sticky traps for fruit flies page.
Replace a full or dusty card
Replace the card when it is full, dusty, or no longer sticky. Plant & Pest and Super Ninja use that test, and it is the right test for this set. A board you can no longer see as yellow has little bare glue left. Dust does the same as a crowded sheet.
MSR states up to 3.5 months and GOTRUST states up to 3 months. Those figures are the sellers' own wording, not a laboratory life test, and they are not a reason to keep a black card. Super Ninja's up to three months and Plantura's at least six months describe those brands. Do not copy either figure onto Blooven, lnkey, or any listing that does not state it.
If the yellow is gone in a fortnight, change the card. If a light card is still tacky weeks later, leave it until the glue dulls. A full card does not end the problem. Larvae in the compost never meet the glue, so a new sheet only resets the adult count. Blooven's listing says watering does not affect the adhesive. That is one seller's claim, and it does not rescue glue buried in wet compost. Angle the card, as MSR describes. If a commercial glasshouse crop keeps producing flies, ask the nursery.
Common questions
Do I peel one side or both?
Peel every cover. MSR's listing says both covers, and Super Ninja and Baby Bio say the same for their own cards. One peeled face still leaves a dead side if the sheet is coated twice. Check the edges after the first film lifts. A card that stays smooth after a day indoors usually still has film on it.
How far into the compost should the card go?
Push the card in only far enough for it to stand, with the yellow glue just above the compost. Gardeners' World wants the trap near soil level, on a cane or hung close to the plant. Burying the glue turns the sheet into a stake. Blooven's slide-in method still leaves the catching face in the air. A cane holds the card if the compost is too loose to grip it.
Can I hang the card in the foliage instead?
Hang it among the leaves when the insects are flying there, and keep fungus-gnat cards low. GOTRUST and flintronic use a tie through the hole. Lunyoutrio uses stakes or adhesive hooks. Set a greenhouse card just above the leaves and keep the glue off the leaf. Flies leaving compost still want the card near soil level.
When do I replace a yellow sticky trap?
Replace it when the board is full, dusty, or no longer sticky, which is when you can no longer see yellow. MSR's up to 3.5 months and GOTRUST's up to 3 months are seller claims for those listings only. They are not a laboratory result, and they do not apply to Blooven or lnkey. A full card does not mean the larvae have gone.
How do I keep glue off hands, leaves and pets?
Do not touch the glue, which a TRIITECH review warned against, and keep children and pets away, as the lnkey seller states. Keep the adhesive off leaves, as Plant & Pest advises. A UK review of an aonova card described glue on a dog's tail when the sheet was at ground level, so raise the card or move the pot. If glue is already in fur, ask a vet. These listings do not describe the glue as safe on skin.
Related pages
Sources
Public UK sources for fungus gnats, whitefly, thrips monitoring, and what a monitoring trap may claim. Listings are the amazon.co.uk captures for these eleven ASINs, not a live reload on 17 October 2026. Prices on amazon.co.uk move.
- RHS, fungus gnats (retrieved 17 October 2026)
- RHS, glasshouse whitefly (retrieved 17 October 2026)
- RHS, indoor sap-feeding insects (retrieved 17 October 2026)
- HSE, insect monitoring traps (retrieved 17 October 2026)
- AHDB, thrips monitoring (retrieved 17 October 2026)
- Gardeners' World, house plant flies (retrieved 17 October 2026)
- Which?, fungus gnats (retrieved 17 October 2026)
- Citizens Advice, faulty goods (retrieved 17 October 2026)