There are many natural predators that eat aphids, including: hummingbirds, lacewing bugs, ladybugs, predator wasps, etc.
Ladybugs, also called lady beetles or ladybird beetles, are from the beneficial group of insects. They feast on garden pests in both the larval and adult stages, devouring thousands of aphids in its lifetime.
Ladybugs are able to consume 50 to 60 aphids per day. They will also eat many other types of insects and larvae such as scales, spider mites, mealy bugs, leaf hoppers, mealybugs and various types of soft-bodied insects. They will also consume the eggs of other insects, such as the European Corn Borer and the Colorado Potato Beetle.
Adult lady beetles are round beetles measuring no more than 3/8″ in length. They can be orange, red, or black with or without spots. Their larvae remind me of tiny alligators in shape, their tiny spiked projections and the orange stripes on its body; which may be black or blue. Their eggs are whitish/yellowish in color, oval-shaped and found in clusters. They lay their eggs where aphids are nearby so the larvae can feed on the insects as they emerge from their eggs.
The only time this insect may be considered a ‘pest’ is around fall time as the weather gets cooler; the Asian lady beetles will enter homes and other buildings looking for a warm place for the winter.
Check out the video I took below in my greenhouse. Below is a video I took in my greenhouse of a ladybug larvae eating an aphid: