^^^^^what patrick said^^^^
and a couple of additional points...
ants...in my garden, if I find ants on plants, aphids are there also...after you get to know the signs, it is a matter of looking at the leaves to see if you have aphids...if you do, you will see a shiny substance (honeydew and excrement) on the tops of the leaves...if you look under the leaf above the shiny stuff, you will find your aphids...eradicate the ants and you have gone a long way towards preventive aphid control...
aphid life cycle...as you probably know, aphids are born pregnant without the pleasure of sex...
I googled this quote.... "A newly born aphid becomes a reproducing adult within about a week and then can produce up to 5 offspring per day for up to 30 days!"...in order to get them all, you have to treat weekly or twice a week for a month or more if you want to get them all...
If you don't have ladybugs, green lace wings, or praying mantis in your garden, you need to get some....