The plant was brought into the house because it was too cold outside for the plant to survive. Afterwards the plant was found to be covered with aphids. Some of the worst infested parts of the plant were removed and thrown out.
I wonder if someone knows how to get rid of the aphids without killing the plant.
they tend to be easily unseated from their position. maybe if you shook it off outside perodically. manually management might be easy since it will be inside and not subject to much reinfestation. maybe some sticky traps too? when dealing with aphids outside I would just blast the plant with water regularly for a few days until the numbers seem to subside to a number the plant can deal with.
1. use a diluted soapy water spray on the plant, using a mild, natural soap of course -- do what you can to try not to get soap in the soil of a potted plant (not as much of an issue with outdoor, non-potted plants). Be sure to get the underside of the leaves. Soap removes the waxy coating on the aphids which dehydrates them and then they die. Usually soap doesn't bother the plant, but without rain, it might be good to rinse the plant a day or two after the aphids die off. Definitely not a good idea on some types of plants, which is probably why "soil" asked what type of plant.
2. slide them off with thumb and forefinger and squish them (or collect them and wash them down the drain if you're squeamish). Safest for soil and plant, but might have to do daily until you get them all, or might be hard if they're hiding in stem and leaf joints, etc. Similar to Leah's idea, except more up close and personal than a blast of water. You know, you could possibly do a water blast in the shower. Again, depending on the plant.
Another line of thought is that strong, healthy plants tend to not get aphids. But now that you are inside, the aphids might have no other choice.
The outdoor solution is ladybugs or lacewing. Preferably the larvae. Either can be indoors, but .... I would think they would disappear quickly. Or they could just end up being annoying.
I do know of at least one case where somebody brought a bunch of ladybugs indoors to get rid of aphids on houseplants. Effective. And some people were bothered by it.
The soapy stuff does work, but I have lots of reservations about it. I would google for recipes that are very light on the soap and add in garlic and/or pepper. I would think a soft bodied sugar loving creature would not care for garlic and/or pepper - and I've heard of those before.
recently we collected pine cones and used a dropper and essential oil (peppermint and anise) to scent them. just a fun little project. we now have several baskets of strong smelling pinecones in the house. if you hover over one of those baskets..particulary the peppermint one that may have ended up with a bit "extra" on the cones due to my young helper.....it is too much......I wonder if rag placed below the plant with a goodly amount of some aromatic essential oil in it would make it less hospitable. i certainly can't hover over the "peppermint cones basket" for long.....clove oil is supposed to be an insect detterent and is in many "natural" insect repelents..it might be worth a shot.....at the very least it sill make your home smell good
1) Along the line of the "easily dislodged" thing, above - spraying water will usually wash them off of the plant.
2) Maybe it is a good time to repot the plant. A bigger pot and better soil would lead to a healthier plant that makes the aphids less interested. Repotting is a stress to the plant, so do it only if it is time. Another idea is to add organic matter, or maybe it isn't getting good fertilizer.
And here is a possible permie idea: what about planting something in the pot that will help? Chives?
Would be good to know the size and type of plant to help with the problem.
There are some plants that I will just pull out of the pot and essentially give a bath to but those are pretty indestructible house plants that are not even planted in soil and need dusting anyway.
There are other plants that will be far more sensitive. I would probably (if the plant is a size to be able to do it) place the pot in a plastic bag and tie around the stem of the plant to keep from saturating the soil, then take the whole thing into the shower (hopefully you have a hand heald shower sprayer) and give the plant a good shower spraying the under sides of the leaves and everything well with cool to just below luke warm water. Hopefully that way you can get rid of most of the aphids. Then perhaps give the plant a dose of something like sea weed extract or worm tea before removing it from the tub.
Squish what you can find, wont take but a few minutes.
Start a couple of peas (early alaska, little marvel, green arrow for example) in a cup beside your plant. Aphids love peas as much as penguins love ice cream. The pea plant will grow rapidlay and serve as a decoy. If the aphids come back, there is a good chance they will migrate to the pea. The are a social bug and will have their town meetings mostly on one plant. Toss out the plant along with the aphid Whoville, start another.
Seed the Mind, Harvest Ideas.
Companion Planting Guide by World Permaculture Association