What pests does rubbing alcohol kill?

Rubbing Alcohol or Isopropyl Alcohol is a home remedy for soft-bodied plant pests with a waxy coating, including mealybugs, aphids, spider mites and scale. See the full directions for use below for different dilution rates, application and treatment frequency depending on the pest.

Is rubbing alcohol the same as isopropyl alcohol?

Yes and no. Rubbing alcohol contains isopropyl alcohol, but at a lower concentration. Rubbing alcohol varies between brands but for use to kill pests on indoor plants, the general advice is to avoid going over 70% alcohol. Perrigo Rubbing Alcohol (that's this product you're on now), is 70% strength isopropyl alcohol mixed with distilled water.

How to use rubbing alcohol to treat mealybugs, aphids, scale and spider mites

READ BEFORE FIRST USE: Check precautions (below), as some plants are more sensitive to alcohol than others. Following are shortened directions for use by pest, however it's important to note these are a guide only because rubbing alcohol is a 'DIY treatment / home remedy' for plant pests, so you won't find this on the label. This is off-label use meaning there are no guarantees...

You can also search 'rubbing alcohol + [pest name]' online for more advice. For best results use a super fine spray mister for better coverage and better contact with the leaf surface and pests.

MEALYBUGS: Isolate the plant. Dip cotton bud, cotton pad or similar in 70% rubbing alcohol (undiluted). Press on-to then wipe off visible adults for instant kill. Then treat the entire plant with a mix of 1 part rubbing alcohol with 1 part water and a couple of drops of insecticidal soap.

Stir mixture then spray foliage thoroughly, including stems and (very lightly), the top of the soil (never pour mixture on to roots or drench the soil). Wait 5 to 10 minutes. Spray off or rinse off with plain water. Repot if needed. Repeat fortnightly until gone (check detailed mealybugs treatment directions here).

SCALE: Isolate the plant. For a light infestation, dip cotton pad or cotton bud in rubbing alcohol (undiluted), and dab then wipe off visible scale one by one. For a more serious infestation, spot treat (undiluted), and also spray the rest of the plant with diluted rubbing alcohol. Mix 1 cup rubbing alcohol with a tablespoon of insecticidal soap and 1 litre of water and spray foliage and stems. Repeat every 3 days for at least 2 weeks.

SPIDER MITES: Isolate the plant. Use undiluted rubbing alcohol for best results, or for sensitive plants (test first), mix 1 part rubbing alcohol to 3 parts water, and wipe leaves (top and bottom), with mixture.

For best results follow-up with the diluted mixture in a spray bottle, applied to foliage, top and bottom. Leave for 1 to 3 hours and rinse off dead mites with plain water. Another popular combination against spider mites is 1 tablespoon of insecticidal soap, 1 litre of water and 1 cup of rubbing alcohol. Mix and apply as both a wipe and a spray, rinse off 1 hour later. Repeat every 3 days for at least 2 weeks.

APHIDS: Isolate the plant. Make an insecticidal soap and alcohol solution, using 2 parts rubbing alcohol, 5 parts water and 1 tablespoon of soap. Spray foliage and stems liberally. Although time-consuming and fiddly with how small aphids are, you can also spot treat aphids directly using undiluted rubbing alcohol on a cotton bud or similar.

Rubbing alcohol kills aphids almost instantly on contact but a spray treatment is usually needed for anything except a very light infestation caught early. Spray or spot treat (or both), every 2 to 3 days, for at least 2 weeks.

Is rubbing alcohol safe on all plants?

On the whole, yes, however some plants are more sensitive than others. Note that ALL plants under moisture stress are more sensitive to all sprays, so if a plant is thirsty / dry, water first and let it recover from moisture stress before treatment.

Unless you're confident your plant is not sensitive to rubbing alcohol or insecticial soap (or if you don't know), dilute as per the directions below, and do a test patch first on a leaf or two (avoid getting rubbing alcohol on roots).

How to do a test spray: Apply to one or two leaves and wait at least 2 days / 48 hours. Look for signs such as leaf scorch. If you do see a reaction, either do not treat the rest of the plant, or dilute more than usual and patch-test again before treating the rest of the plant.

When to apply: The same as all insect treatments, best to apply early morning or early evening, and apply on a day not expected to reach over 30 degrees. Plants being treated should be isolated. Avoid direct sun on leaves during treatment until dry.

Treating pests comes with risks: There is always some risk involved in treating any plant with any insecticide or non-insecticidal treatment (including soap). Some leaf browning, wilting or leaf drop are common. This should come right relatively quickly, once the pests are eradicated, and your plant can put out healthy growth again, without pests damaging foliage or stunting growth. When using soap, ideally only use insecticidal soap like Yates Natrasoap, or if you can't get it, use plain Castile liquid soap with no oils or other additives. Never use dish soap (this is why).

After use for ALL pests: Once poured out of the container, do not pour leftovers back in even if you didn't dilute the rubbing alcohol. Best to make up only what's needed and safely disgard leftovers (such as spraying leftovers on plants outdoors).

IMPORTANT REMINDER: Please note using rubbing alcohol for plants is what's called 'off label use'. Meaning it's not what rubbing alcohol was intended for, just a popular repurposed use by houseplant hobbyists. That means results are not guaranteed, and there's no guarantee that it won't harm plants, so please do take the precautions mentioned above to test spray first for sensitive plants or if you're unsure.

NEW

Perrigo 70% Isopropyl Rubbing Alcohol - Mealybugs, Aphids, Spider Mites & Scale - 500ml

Yates Nature's Way Nutrasoap READY-TO-USE - Insecticidal Soap for Spider Mites, Aphids, Whitefly - 750ml + Spray Mister included

Yates Nature's Way Nutrasoap CONCENTRATE - Insecticidal Soap for Spider Mites, Aphids, Whitefly - 200ml (makes 10 litres)