Without having to source lady bugs, aphids are relatively easy to control.
There are hundreds of variants of this home made aphid and mite controller. It's basically known as white oil emulsion and can also be bought at nurseries but that one is usually not considered organic because it contains petro based oils.
One cup of vegetable oil such as canola/rape seed oil
half a cup of water
Mix in a blender
then add a good squirt of dish-washing liquid, shake well and store in a bottle.
This is a concentrate and can be used at a ratio of 50:1 in a spraying bottle with water.That's about a tablespoon for one litre or 2 pints of water.
Spray on both sides of the leaves and repeat every 4 weeks.
It's best not to spray on hot days.
Here's yet another recipe...
It is true that ladybugs eat them. But you have to lay them on the ground at night so they kind of make a path in the dirt. Otherwise, they are known to fly away to some other garden. You can buy a tine plastic carton of ladybugs from specific garden stores. You will find them in a refrigerated section.
It's possible to buy frozen, living ladybugs in a plastic box? I must say that this sounds extremely cruel Poor little ladybugs, I feel very sorry for them. I don't like insects, but I hate seeing them suffer.
I was reading an article about the people in India using cola drinks like Coke and Pepsi as a pesticide. Even though both companies claimed that there is nothing in either cols drink that would work as a pesticide; the farmers that are using it claim that it works as well as regular pesticide, but is much cheaper to use.
apparently, they just mix it with water and spray it on the plants, like their rice crops.
No one is quite sure why it works, but it does seem safer than using dangerous chemicals. One theory is that the sugar in the cola attracts ants, and the ants eat the aphids.