Ladybugs are cute, and they do eat aphids, but they also fly away!
If you want to use beneficial insects, contact a supplier, and ask for recommendations based on your growing specifics.
They'll likely suggest something that sticks around longer than these red beauties.
The correct species, quantity, and release method will depend on several factors, such as your cultivation method, pest pressure, and planting density.
For example, if your plants are touching each other, the insects will be able to crawl onto other plants, allowing you to use fewer insects. If your plants aren't touching, anticipate needing to apply beneficials to every plant, either by sprinkling them onto the crop manually or hanging sachets on individual plants.
Skip the guesswork and ask a professional from an insect supplier like BioBest or Koppert to create a release program for your crop. The insight will prove invaluable, and it's often free.