There are a lot of insects that can eliminate them. Some of them are ladybugs, parasitic wasps, lacewings, etc. You can even order these insects online. Another method to keep Aphids away is planting catnip, mustard, and nasturtium next to the plants because Aphids don't like the smell. And for shade and fruit trees, you can use the horticultural spray as preventive maintenance because it will help to kill overwintering Aphids' eggs.