Is a Pre-emptive attack on aphids okay?

Each year, I put my young pomegranate bonsai outside during the warm months and keep it indoors during the winter. It usually puts on good growth while it's outside. This year was an exception as there was very little new growth. When I brought it indoors I discovered why - aphids. It took me close to a month to finally remove these buggers by spraying every four days or so with a soap/water mixture and also picking the aphids off every day using sticky clear packing tape. The plant then sent out some fresh growth and it looks like it is doing much better. My question is this - next season, while the plant is outdoors again in the warm weather, is it okay to spray the plant with the soap/water solution every week or so to keep the aphids from attacking the plant? Or could that hurt the plant in some way?

Hello Barry M, this is such a common problem yet so easy to cure. My tried and tested method is to be vigilant throughout the warm weather and when you spot either the critters or ants around the plant spray a fine mist liberally with a mixture of one capfull of surgical spirits, two squirts of dishwashing liquid to a litre of water, mix well until it froths.. Results in aphid clear plant by the next day, no problem or side effects. Be sure to spray the underside too....

Charlie....

Thanks Charlie.

Hi Barry,

I live in Central MD and I notice the aphids are out as soon as it warms up. Your Pom must have been infested all season. Follow Charlie's advice.

I haven't had any problems getting rid of them either and have used a home made insecticidal soap like Charlie's. A bonus to the recipe is no or very low toxicity, you won't hurt the bees.

I think the soap solution would only kill adult insects on contact, therefor having no effect until they show up. I like Charlie's idea.

That is right, it will only kill the adults. You need to spray every 10 days to get the newly hatched ones. I use a product called SB Invigorator, it has similar properties, it is excellent.

Thanks all for your suggestions/comments. Since I submitted my question I've come across websites in which it's stated that soapy water can remove protective coating from leaves and can, thus, harm a plant. But I've never found that to be a problem with my dwarf pomegranate. Maybe I should only spray occasionally? I'll also look into the SB Invigorator (thanks Geoff). BTW, I have found that dwarf pomegranates are very susceptible to whiteflies. They seem to show up every year around the first of September. So I make sure to bring the tree indoors for the season in late August. It's a shame that the tree loses a month or two of good growing time but the whiteflies are so darn difficult to get rid of (much harder than aphids) that I can't take a chance. Whiteflies leave these hard to see/eradicate tiny eggs. Systemics or any pesticides are out of the question (my wife is absolutely set against them). Anyway, if anyone has a suggestion how to keep the whiteflies away too (without chemicals) that would be great.

I have never heard anyone say that soap removes any coating from leaves, however I do know that you have to be very careful to use a very weak dosage.
There are some varieties of Fuchsia for example that will be severely damaged by even a very weak solution. But as I said the important thing is to repeat every 10 days.

Barry M, the soap/surgical spirits in water solution is really worth a try on whiteflies too. It does a good job of ridding them as well as scale insects. You must be vigilant and wet the underside of the leaves too. I have used this without any ill effects on everything from fruiting trees, succulents, ficus, hibiscus, elms, hawthorn etc..

Charlie..

Hundred21 wrote:Barry M, the soap/surgical spirits in water solution is really worth a try on whiteflies too. It does a good job of ridding them as well as scale insects. You must be vigilant and wet the underside of the leaves too. I have used this without any ill effects on everything from fruiting trees, succulents, ficus, hibiscus, elms, hawthorn etc..

Charlie..

Will do - thanks Charlie.