Insecticidal soap: what it kills and what it does not
100 of 100 species in this database need it
100 of our 100 species need it. Hold a sheet of white paper under the leaves and tap. Typically $10 to $22.
The test, before you buy anything
Hold a sheet of white paper under the leaves and tap. Moving specks mean spider mites. Cottony white lumps in the leaf joints mean mealybugs. Hard brown bumps that do not brush off mean scale. If you find nothing, you have a care problem rather than a pest problem, and soap will not fix it.
Yes
Worth buying. Worth keeping before you need it. The gap between noticing a pest and treating it is where an infestation is won or lost.
Typical price $10–$22 ready-to-use spray bottle. Hand-checked range, not a live price, last verified 2026-09-12.
We hold no merchant relationships, so nothing here is a commission link.
What it actually is
Potassium salts of fatty acids. It kills soft-bodied insects on contact by breaking down their outer layer, and has no residual action at all — which is why coverage and repetition matter more than strength.
What to avoid
It does nothing to eggs, so a single application always fails. Treat weekly for a month to catch each hatch. Scale in its armoured adult stage is largely immune and has to be scraped off first. And dish soap is not the same thing; it strips leaf cuticle.
Species in this database that need it
These species have soft-bodied pests recorded against them — the ones soap actually works on.
| Plant | Why it qualifies | Water | Difficulty |
|---|---|---|---|
| Swiss cheese plantMonstera deliciosa | spider-mites, thrips, mealybugs | 7–10d | Easy |
| Snake plantDracaena trifasciata | mealybugs, spider-mites | 14–21d | Easy |
| PothosEpipremnum aureum | mealybugs, spider-mites | 7–14d | Easy |
| ZZ plantZamioculcas zamiifolia | mealybugs | 14–21d | Easy |
| Peace lilySpathiphyllum wallisii | mealybugs, spider-mites, aphids | 5–7d | Easy |
| Spider plantChlorophytum comosum | spider-mites, aphids | 7–10d | Easy |
| Fiddle leaf figFicus lyrata | spider-mites, mealybugs | 7–12d | Demanding |
| Parlor palmChamaedorea elegans | spider-mites, mealybugs | 7–10d | Easy |
| Cast iron plantAspidistra elatior | spider-mites | 10–14d | Easy |
| Baby rubber plantPeperomia obtusifolia | mealybugs | 9–14d | Easy |
| Rubber plantFicus elastica | spider-mites | 7–14d | Easy |
| Corn plantDracaena fragrans | mealybugs, spider-mites | 10–18d | Easy |
| Heartleaf philodendronPhilodendron hederaceum | aphids, mealybugs | 7–12d | Easy |
| Chinese evergreenAglaonema commutatum | mealybugs, spider-mites | 9–16d | Easy |
| Prayer plantMaranta leuconeura | spider-mites | 4–8d | Moderate |
| Boston fernNephrolepis exaltata | spider-mites | 3–6d | Demanding |
| English ivyHedera helix | spider-mites, aphids | 6–11d | Moderate |
| Jade plantCrassula ovata | mealybugs | 14–28d | Easy |
| Aloe veraAloe vera | mealybugs | 14–28d | Easy |
| Zebra haworthiaHaworthiopsis attenuata | mealybugs | 14–24d | Easy |
| Christmas cactusSchlumbergera truncata | mealybugs | 7–14d | Easy |
| Moth orchidPhalaenopsis amabilis | mealybugs | 5–10d | Easy |
| Chinese money plantPilea peperomioides | spider-mites | 6–11d | Easy |
| Wax plantHoya carnosa | mealybugs, aphids | 10–18d | Easy |
| Ponytail palmBeaucarnea recurvata | spider-mites | 14–30d | Easy |
| Dumb caneDieffenbachia seguine | spider-mites, mealybugs | 7–12d | Easy |
| Flamingo flowerAnthurium andraeanum | mealybugs | 6–10d | Moderate |
| Arrowhead vineSyngonium podophyllum | spider-mites, aphids | 6–11d | Easy |
| Inch plantTradescantia zebrina | spider-mites, aphids | 5–9d | Easy |
| Polka dot begoniaBegonia maculata | mealybugs, thrips | 5–10d | Moderate |
| African violetStreptocarpus ionanthus | mealybugs, thrips | 5–10d | Moderate |
| African milk treeEuphorbia trigona | mealybugs, spider-mites | 14–28d | Easy |
| Flaming KatyKalanchoe blossfeldiana | mealybugs, aphids | 9–16d | Easy |
| Burro’s tailSedum morganianum | mealybugs, aphids | 14–28d | Easy |
| Mexican snowballEcheveria elegans | mealybugs, aphids | 12–24d | Moderate |
| Spineless yuccaYucca gigantea | mealybugs | 14–24d | Easy |
| Asparagus fernAsparagus setaceus | spider-mites | 4–9d | Easy |
| Nerve plantFittonia albivenis | spider-mites | 3–6d | Moderate |
| Maidenhair fernAdiantum raddianum | mealybugs | 2–5d | Difficult |
| Florist’s cyclamenCyclamen persicum | spider-mites, thrips | 4–9d | Demanding |
| Dragon treeDracaena marginata | mealybugs, spider-mites | 10–18d | Easy |
| Lucky bambooDracaena sanderiana | mealybugs, spider-mites | 5–10d | Easy |
| Weeping figFicus benjamina | spider-mites | 7–12d | Moderate |
| Dwarf umbrella treeHeptapleurum arboricola | spider-mites, mealybugs | 7–14d | Easy |
| Areca palmDypsis lutescens | spider-mites, mealybugs | 5–10d | Moderate |
| Kentia palmHowea forsteriana | spider-mites | 8–14d | Easy |
| Lady palmRhapis excelsa | spider-mites | 8–14d | Easy |
| Bird of paradiseStrelitzia reginae | spider-mites, mealybugs | 7–12d | Moderate |
| Calathea orbifoliaGoeppertia orbifolia | spider-mites | 4–8d | Demanding |
| Rattlesnake plantGoeppertia lancifolia | spider-mites | 4–8d | Moderate |
| Triostar stromantheStromanthe sanguinea | spider-mites | 4–8d | Demanding |
| Watermelon peperomiaPeperomia argyreia | mealybugs | 7–14d | Easy |
| Polka dot plantHypoestes phyllostachya | aphids, spider-mites | 4–7d | Easy |
| String of pearlsCurio rowleyanus | mealybugs, aphids | 12–21d | Demanding |
| String of heartsCeropegia woodii | mealybugs, aphids | 10–18d | Easy |
| Mini monsteraRhaphidophora tetrasperma | spider-mites, mealybugs, thrips | 5–10d | Easy |
| Satin pothosScindapsus pictus | spider-mites, mealybugs | 7–12d | Easy |
| Swiss cheese vineMonstera adansonii | spider-mites, thrips, mealybugs | 6–11d | Easy |
| African mask plantAlocasia × mortfontanensis | spider-mites, mealybugs, thrips | 5–10d | Demanding |
| CrotonCodiaeum variegatum | spider-mites, mealybugs | 6–11d | Moderate |
| Ti plantCordyline fruticosa | spider-mites, mealybugs | 6–11d | Moderate |
| Bird’s nest fernAsplenium nidus | mealybugs | 4–9d | Easy |
| Staghorn fernPlatycerium bifurcatum | mealybugs | 7–14d | Moderate |
| Purple shamrockOxalis triangularis | spider-mites, aphids | 6–11d | Easy |
| Scarlet starGuzmania lingulata | mealybugs | 7–14d | Easy |
| Air plantTillandsia ionantha | mealybugs | 5–10d | Moderate |
| Golden barrel cactusEchinocactus grusonii | mealybugs | 18–35d | Easy |
| Ladyfinger cactusMammillaria elongata | mealybugs | 14–30d | Easy |
| Elephant bushPortulacaria afra | mealybugs, spider-mites | 10–21d | Easy |
| Crown of thornsEuphorbia milii | mealybugs, spider-mites | 10–21d | Easy |
| Tree philodendronPhilodendron bipinnatifidum | spider-mites, mealybugs | 7–12d | Easy |
| Calla lilyZantedeschia aethiopica | aphids, spider-mites | 4–8d | Moderate |
| CaladiumCaladium bicolor | spider-mites, aphids, thrips | 4–9d | Demanding |
| Zebra alocasiaAlocasia zebrina | spider-mites, mealybugs, thrips | 5–10d | Demanding |
| Blushing philodendronPhilodendron erubescens | spider-mites, thrips, mealybugs | 6–11d | Easy |
| Dragon tail plantEpipremnum pinnatum | spider-mites, mealybugs | 7–12d | Easy |
| Pygmy date palmPhoenix roebelenii | spider-mites, mealybugs | 6–12d | Moderate |
| Bamboo palmChamaedorea seifrizii | spider-mites | 7–12d | Easy |
| Blue star fernPhlebodium aureum | mealybugs | 5–10d | Easy |
| Rabbit’s foot fernDavallia fejeensis | mealybugs | 4–9d | Moderate |
| Table fernPteris cretica | mealybugs | 3–7d | Moderate |
| Bunny ears cactusOpuntia microdasys | mealybugs | 18–35d | Easy |
| Mistletoe cactusRhipsalis baccifera | mealybugs | 7–14d | Easy |
| Fishbone cactusSelenicereus anthonyanus | mealybugs | 7–14d | Easy |
| Ox tongueGasteria bicolor | mealybugs | 14–24d | Easy |
| Tree aeoniumAeonium arboreum | mealybugs, aphids | 9–18d | Moderate |
| Jelly bean plantSedum rubrotinctum | mealybugs, aphids | 12–24d | Easy |
| String of bananasCurio radicans | mealybugs, aphids | 12–21d | Easy |
| Creeping figFicus pumila | spider-mites, mealybugs | 4–9d | Moderate |
| Banyan figFicus benghalensis | spider-mites, mealybugs | 7–14d | Easy |
| Baby’s tearsSoleirolia soleirolii | aphids | 2–6d | Moderate |
| Strawberry begoniaSaxifraga stolonifera | aphids, spider-mites | 5–10d | Easy |
| Lipstick plantAeschynanthus radicans | mealybugs, aphids | 6–11d | Moderate |
| Goldfish plantNematanthus gregarius | mealybugs, aphids, spider-mites | 6–11d | Easy |
| Ripple peperomiaPeperomia caperata | mealybugs | 7–14d | Easy |
| String of turtlesPeperomia prostrata | mealybugs | 9–16d | Moderate |
| Sweetheart hoyaHoya kerrii | mealybugs, aphids | 12–21d | Easy |
| Turtle vineCallisia repens | spider-mites, aphids | 4–9d | Easy |
| Rex begoniaBegonia rex | mealybugs, thrips, spider-mites | 5–10d | Demanding |
| Coffee plantCoffea arabica | mealybugs, spider-mites | 5–10d | Moderate |
This table is filtered from our own species records — recorded soil recipe, humidity floor, light floor, watering interval or growth habit, depending on the product. It is not a list of things a retailer would like to sell you.
Other supplies
- Perlite worth it
- Orchid bark depends
- Cactus and succulent mix depends
- Pumice depends
- Moss pole depends
- Humidifier depends
Sources
- This database's own care records for 100 species — the recorded soil recipes, humidity floors, light floors and watering intervals this table filters on. Each species entry cites its own authorities.
- Missouri Botanical Garden Plant Finder — cultivation and pest records, cited per species
- North Carolina Extension Gardener Plant Toolbox — pest and disease guidance
- ASPCA Animal Poison Control — relevant where a product is used on a plant pets reach
Compiled and edited by Tony Valcarcel · 2026-09-12
Prices are hand-checked ranges stamped manual, not live figures, and they move with
pack size. We do not accept payment for placement and hold no merchant
relationships; there are no commission links on this page. How this is sourced.