Nancy Reading wrote:Sometimes the best answer is to do nothing.....
I suggest that you wait and observe. Watch for wasps and ladybird larvae to come and hoover them up - that'll boost the predator population and reduce the aphid burden next year.
If you have space, plant flowering plants like fennel and daisies to attract more beneficial insects like hoverflies. Their larvae also are great for aphid control and are also good pollinators for many flowers (so you get a better fruit crop too!)
Do nothing but also do all the things. Look up Integrated Pest Management and you will find that most control methods don't have anything to do with direct control. As already mentioned, have healthy plants (compost, manure, mulch, properly sized planting holes, proper watering first year), have healthy environment (plant diversity, ecosystem diversity, insect diversity), have insect habitat. Nature will control the aphids, but there is no need to completely get rid of them.
The Do Nothing part is important to all of this as well. I personally witnessed an aphid boom on some young peaches early in my gardening journey. 7 days later there was a fog of lacewings in the orchard massacring the aphids, followed by ladybugs, followed by bluebirds setting up residence. Over the course of 2 months, all of this came and went in a wave and left me with only peach leaf curl left to contend with (this I did need to control directly with milk and garlic spray for a couple years). The experience was a very in-my-face lesson on patience and observation. Other times in my journey I have Done Nothing and watched things fail, but learned valuable lessons in why and how in the meantime - sometimes a specific plant isn't supposed to be in a specific place and you just haven't figured out why yet.